Adding some logs to help diagnose issue
aaa.aaa.aaa.aaa is the LAN IP for pfSense
xxx.xxx.xxx.xxx is my WAN IP
yyy.yyy.yyy.yyy is my iphone's provider IP
zzz.zzz.zzz.zzz is the internal LAN IP for the PPTP client
Aug 15 00:32:48 pptps: [pt0] LCP: state change Closing --> Initial
Aug 15 00:32:48 pptps: [pt0] LCP: LayerFinish
Aug 15 00:32:48 pptps: [pt0] LCP: Down event
Aug 15 00:32:48 pptps: [pt0] link: DOWN event
Aug 15 00:32:48 pptps: [pt0] PPTP call terminated
Aug 15 00:32:48 pptps: pptp0-0: killing channel
Aug 15 00:32:48 pptps: pptp0: killing connection with yyy.yyy.yyy.yyy 54108
Aug 15 00:32:48 pptps: pptp0: ctrl connection closed by peer
Aug 15 00:32:48 pptps: [pt0] LCP: state change Stopping --> Closing
Aug 15 00:32:48 pptps: [pt0] LCP: Close event
Aug 15 00:32:48 pptps: [pt0] link: CLOSE event
Aug 15 00:32:48 pptps: [pt0] LCP: SendTerminateAck #5
Aug 15 00:32:48 pptps: [pt0] LCP: rec'd Terminate Request #3 (Stopping)
Aug 15 00:32:48 pptps: [pt0] LCP: LayerDown
Aug 15 00:32:48 pptps: [pt0] LCP: SendTerminateAck #4
Aug 15 00:32:48 pptps: [pt0] AUTH: Cleanup
Aug 15 00:32:48 pptps: [pt0] CCP: state change Closing --> Initial
Aug 15 00:32:48 pptps: [pt0] CCP: LayerFinish
Aug 15 00:32:48 pptps: [pt0] CCP: Down event
Aug 15 00:32:48 pptps: [pt0] IPCP: state change Closing --> Initial
Aug 15 00:32:48 pptps: [pt0] closing link "pt0"...
Aug 15 00:32:48 pptps: [pt0] No NCPs left. Closing links...
Aug 15 00:32:48 pptps: [pt0] IPCP: LayerFinish
Aug 15 00:32:48 pptps: [pt0] IPCP: Down event
Aug 15 00:32:48 pptps: [pt0] CCP: LayerDown
Aug 15 00:32:48 pptps: [pt0] error writing len 8 frame to bypass: Network is down
Aug 15 00:32:48 pptps: [pt0] CCP: SendTerminateReq #2
Aug 15 00:32:48 pptps: [pt0] CCP: state change Opened --> Closing
Aug 15 00:32:48 pptps: [pt0] CCP: Close event
Aug 15 00:32:48 pptps: [pt0] IFACE: Down event
Aug 15 00:32:48 pptps: [pt0] IPCP: LayerDown
Aug 15 00:32:48 pptps: [pt0] error writing len 8 frame to bypass: Network is down
Aug 15 00:32:48 pptps: [pt0] IPCP: SendTerminateReq #4
Aug 15 00:32:48 pptps: [pt0] IPCP: state change Opened --> Closing
Aug 15 00:32:48 pptps: [pt0] IPCP: Close event
Aug 15 00:32:48 pptps: [pt0] Bundle up: 0 links, total bandwidth 9600 bps
Aug 15 00:32:48 pptps: [pt0] AUTH: Accounting data for user blablabla: 227 seconds, 2936 octets in, 4160 octets out
Aug 15 00:32:48 pptps: [pt0] LCP: state change Opened --> Stopping
Aug 15 00:32:48 pptps: [pt0] LCP: rec'd Terminate Request #2 (Opened)
Aug 15 00:29:07 pptps: [pt0] IFACE: Up event
Aug 15 00:29:07 pptps: xxx.xxx.xxx.xxx -> zzz.zzz.zzz.zzz
Aug 15 00:29:07 pptps: [pt0] IPCP: LayerUp
Aug 15 00:29:07 pptps: [pt0] IPCP: state change Ack-Sent --> Opened
Aug 15 00:29:07 pptps: IPADDR xxx.xxx.xxx.xxx
Aug 15 00:29:07 pptps: [pt0] IPCP: rec'd Configure Ack #3 (Ack-Sent)
Aug 15 00:29:06 pptps: IPADDR xxx.xxx.xxx.xxx
Aug 15 00:29:06 pptps: [pt0] IPCP: SendConfigReq #3
Aug 15 00:29:06 pptps: COMPPROTO VJCOMP, 16 comp. channels, no comp-cid
Aug 15 00:29:06 pptps: [pt0] IPCP: rec'd Configure Reject #2 (Ack-Sent)
Aug 15 00:29:06 pptps: COMPPROTO VJCOMP, 16 comp. channels, no comp-cid
Aug 15 00:29:06 pptps: IPADDR xxx.xxx.xxx.xxx
Aug 15 00:29:06 pptps: [pt0] IPCP: SendConfigReq #2
Aug 15 00:29:05 pptps: [pt0] IPCP: state change Req-Sent --> Ack-Sent
Aug 15 00:29:05 pptps: SECDNS 8.8.8.8
Aug 15 00:29:05 pptps: PRIDNS aaa.aaa.aaa.aaa
Aug 15 00:29:05 pptps: IPADDR zzz.zzz.zzz.zzz
Aug 15 00:29:05 pptps: [pt0] IPCP: SendConfigAck #2
Aug 15 00:29:05 pptps: SECDNS 8.8.8.8
Aug 15 00:29:05 pptps: PRIDNS aaa.aaa.aaa.aaa
Aug 15 00:29:05 pptps: zzz.zzz.zzz.zzz is OK
Aug 15 00:29:05 pptps: IPADDR zzz.zzz.zzz.zzz
Aug 15 00:29:05 pptps: [pt0] IPCP: rec'd Configure Request #2 (Req-Sent)
Aug 15 00:29:05 pptps: [pt0] rec'd unexpected protocol IPV6CP, rejecting
Aug 15 00:29:05 pptps: SECDNS 8.8.8.8
Aug 15 00:29:05 pptps: PRIDNS aaa.aaa.aaa.aaa
Aug 15 00:29:05 pptps: IPADDR zzz.zzz.zzz.zzz
Aug 15 00:29:05 pptps: [pt0] IPCP: SendConfigNak #1
Aug 15 00:29:05 pptps: NAKing with 8.8.8.8
Aug 15 00:29:05 pptps: SECDNS 0.0.0.0
Aug 15 00:29:05 pptps: NAKing with aaa.aaa.aaa.aaa
Aug 15 00:29:05 pptps: PRIDNS 0.0.0.0
Aug 15 00:29:05 pptps: NAKing with zzz.zzz.zzz.zzz
Aug 15 00:29:05 pptps: IPADDR 0.0.0.0
Aug 15 00:29:05 pptps: [pt0] IPCP: rec'd Configure Request #1 (Req-Sent)
Aug 15 00:29:05 pptps: Decompress using: mppc (MPPE(128 bits), stateless)
Aug 15 00:29:05 pptps: Compress using: mppc (MPPE(128 bits), stateless)
Aug 15 00:29:05 pptps: [pt0] CCP: LayerUp
Aug 15 00:29:05 pptps: [pt0] CCP: state change Ack-Rcvd --> Opened
Aug 15 00:29:05 pptps: 0x01000040:MPPE(128 bits), stateless
Aug 15 00:29:05 pptps: MPPC
Aug 15 00:29:05 pptps: [pt0] CCP: SendConfigAck #2
Aug 15 00:29:05 pptps: 0x01000040:MPPE(128 bits), stateless
Aug 15 00:29:05 pptps: MPPC
Aug 15 00:29:05 pptps: [pt0] CCP: rec'd Configure Request #2 (Ack-Rcvd)
Aug 15 00:29:04 pptps: [pt0] CCP: state change Req-Sent --> Ack-Rcvd
Aug 15 00:29:04 pptps: 0x01000040:MPPE(128 bits), stateless
Aug 15 00:29:04 pptps: MPPC
Aug 15 00:29:04 pptps: [pt0] CCP: rec'd Configure Ack #1 (Req-Sent)
Aug 15 00:29:04 pptps: [pt0] IPCP: rec'd Terminate Ack #1 (Req-Sent)
Aug 15 00:29:04 pptps: 0x01000040:MPPE(128 bits), stateless
Aug 15 00:29:04 pptps: MPPC
Aug 15 00:29:04 pptps: [pt0] CCP: SendConfigNak #1
Aug 15 00:29:04 pptps: 0x01000060:MPPE(40, 128 bits), stateless
Aug 15 00:29:04 pptps: MPPC
Aug 15 00:29:04 pptps: [pt0] CCP: rec'd Configure Request #1 (Req-Sent)
Aug 15 00:29:04 pptps: 0x01000040:MPPE(128 bits), stateless
Aug 15 00:29:04 pptps: MPPC
Aug 15 00:29:04 pptps: [pt0] CCP: SendConfigReq #1
Aug 15 00:29:04 pptps: [pt0] CCP: state change Starting --> Req-Sent
Aug 15 00:29:04 pptps: [pt0] CCP: Up event
Aug 15 00:29:04 pptps: COMPPROTO VJCOMP, 16 comp. channels, no comp-cid
Aug 15 00:29:04 pptps: IPADDR xxx.xxx.xxx.xxx
Aug 15 00:29:04 pptps: [pt0] IPCP: SendConfigReq #1
Aug 15 00:29:04 pptps: [pt0] IPCP: state change Starting --> Req-Sent
Aug 15 00:29:04 pptps: [pt0] IPCP: Up event
Aug 15 00:29:04 pptps: [pt0] CCP: LayerStart
Aug 15 00:29:04 pptps: [pt0] CCP: state change Initial --> Starting
Aug 15 00:29:04 pptps: [pt0] CCP: Open event
Aug 15 00:29:04 pptps: [pt0] IPCP: LayerStart
Aug 15 00:29:04 pptps: [pt0] IPCP: state change Initial --> Starting
Aug 15 00:29:04 pptps: [pt0] IPCP: Open event
Aug 15 00:29:04 pptps: [pt0] Bundle up: 1 link, total bandwidth 64000 bps
Aug 15 00:29:04 pptps: [pt0] LCP: authorization successful
Aug 15 00:29:04 pptps: [pt0] CHAP: sending SUCCESS len:42
Aug 15 00:29:04 pptps: Reply message: S=6755F6CB45EC2F39B77C5202F5D7A7C69A9EC717
Aug 15 00:29:04 pptps: Response is valid
Aug 15 00:29:04 pptps: [pt0] CHAP: ChapInputFinish: status undefined
Aug 15 00:29:04 pptps: [pt0] AUTH: Auth-Thread finished normally
Aug 15 00:29:04 pptps: [pt0] AUTH: INTERNAL returned undefined
Aug 15 00:29:04 pptps: [pt0] AUTH: Trying INTERNAL
Aug 15 00:29:04 pptps: [pt0] AUTH: Auth-Thread started
Aug 15 00:29:04 pptps: Name: "blablabla"
Aug 15 00:29:04 pptps: [pt0] CHAP: rec'd RESPONSE #1
Aug 15 00:29:04 pptps: [pt0] LCP: LayerUp
Aug 15 00:29:04 pptps: [pt0] CHAP: sending CHALLENGE len:17
Aug 15 00:29:04 pptps: [pt0] LCP: auth: peer wants nothing, I want CHAP
Aug 15 00:29:04 pptps: [pt0] LCP: state change Ack-Sent --> Opened
Aug 15 00:29:04 pptps: AUTHPROTO CHAP MSOFTv2
Aug 15 00:29:04 pptps: MAGICNUM b2dd1f0a
Aug 15 00:29:04 pptps: MRU 1500
Aug 15 00:29:04 pptps: PROTOCOMP
Aug 15 00:29:04 pptps: ACFCOMP
Aug 15 00:29:04 pptps: [pt0] LCP: rec'd Configure Ack #3 (Ack-Sent)
Aug 15 00:29:03 pptps: AUTHPROTO CHAP MSOFTv2
Aug 15 00:29:03 pptps: MAGICNUM b2dd1f0a
Aug 15 00:29:03 pptps: MRU 1500
Aug 15 00:29:03 pptps: PROTOCOMP
Aug 15 00:29:03 pptps: ACFCOMP
Aug 15 00:29:03 pptps: [pt0] LCP: SendConfigReq #3
Aug 15 00:29:03 pptps: MP SHORTSEQ
Aug 15 00:29:03 pptps: MP MRRU 1600
Aug 15 00:29:03 pptps: [pt0] LCP: rec'd Configure Reject #2 (Ack-Sent)
Aug 15 00:29:03 pptps: ENDPOINTDISC [802.1] 00 15 17 36 ca 1c
Aug 15 00:29:03 pptps: MP SHORTSEQ
Aug 15 00:29:03 pptps: MP MRRU 1600
Aug 15 00:29:03 pptps: AUTHPROTO CHAP MSOFTv2
Aug 15 00:29:03 pptps: MAGICNUM b2dd1f0a
Aug 15 00:29:03 pptps: MRU 1500
Aug 15 00:29:03 pptps: PROTOCOMP
Aug 15 00:29:03 pptps: ACFCOMP
Aug 15 00:29:03 pptps: [pt0] LCP: SendConfigReq #2
Aug 15 00:29:01 pptps: [pt0] LCP: state change Req-Sent --> Ack-Sent
Aug 15 00:29:01 pptps: ACFCOMP
Aug 15 00:29:01 pptps: PROTOCOMP
Aug 15 00:29:01 pptps: MAGICNUM 344d9d4f
Aug 15 00:29:01 pptps: ACCMAP 0x00000000
Aug 15 00:29:01 pptps: [pt0] LCP: SendConfigAck #1
Aug 15 00:29:01 pptps: ACFCOMP
Aug 15 00:29:01 pptps: PROTOCOMP
Aug 15 00:29:01 pptps: MAGICNUM 344d9d4f
Aug 15 00:29:01 pptps: ACCMAP 0x00000000
Aug 15 00:29:01 pptps: [pt0] LCP: rec'd Configure Request #1 (Req-Sent)
Aug 15 00:29:01 pptps: ENDPOINTDISC [802.1] 00 15 17 36 ca 1c
Aug 15 00:29:01 pptps: MP SHORTSEQ
Aug 15 00:29:01 pptps: MP MRRU 1600
Aug 15 00:29:01 pptps: AUTHPROTO CHAP MSOFTv2
Aug 15 00:29:01 pptps: MAGICNUM b2dd1f0a
Aug 15 00:29:01 pptps: MRU 1500
Aug 15 00:29:01 pptps: PROTOCOMP
Aug 15 00:29:01 pptps: ACFCOMP
Aug 15 00:29:01 pptps: [pt0] LCP: SendConfigReq #1
Aug 15 00:29:01 pptps: [pt0] LCP: state change Starting --> Req-Sent
Aug 15 00:29:01 pptps: [pt0] LCP: Up event
Aug 15 00:29:01 pptps: [pt0] link: origination is remote
Aug 15 00:29:01 pptps: [pt0] link: UP event
Aug 15 00:29:01 pptps: [pt0] PPTP: attaching to peer's outgoing call
Aug 15 00:29:01 pptps: [pt0] LCP: LayerStart
Aug 15 00:29:01 pptps: [pt0] LCP: state change Initial --> Starting
Aug 15 00:29:01 pptps: [pt0] LCP: Open event
Aug 15 00:29:01 pptps: [pt0] link: OPEN event
Aug 15 00:29:01 pptps: [pt0] opening link "pt0"...
Aug 15 00:29:01 pptps: [pt0] Accepting PPTP connection
Aug 15 00:29:01 pptps: pptp0: attached to connection with yyy.yyy.yyy.yyy 54108
Aug 15 00:29:01 pptps: PPTP: Incoming control connection from yyy.yyy.yyy.yyy 54108 to xxx.xxx.xxx.xxx 1723
Although this line might be revealing the issue
Aug 15 00:29:05 pptps: [pt0] rec'd unexpected protocol IPV6CP, rejecting