OPENVPN with Virtual IP

[Jamerson]

Dear all,
I have a Pfsense up and running on a hardware 8GB memory/60SSD disk /i5 CPU

I have 4 IP from the ISP
20.50.98.90 till 94

The current IP of the Pfsense WAN is 20.50.98.90 with is handing out the traffic and also having a mail.domain.com DNS pointing to the that IP.
Firewall rules are configured to NAT port 443 to the internal Exchange which is 10.10.20.20
Now we have a second server which need port 443 accessible from the WAN.
So we added a virtual IP on the Pfsense 20.50.98.91 and pointed  the Public DNS name of that machine pointing to the IP 20.50.98.91 and used 1:1 Nat to the internal second server.
We have already configured OPENVPN on the WAN side of the PFSENSE 20.5098.90 which is working fine with internal RADUIS however after we use 1:1 NAT the VPN server stops working. After we delete the 1:1 NAT the VPN server start working.
On the WAN side we have created a rule to allow https/http to the internal servers however its only allow one server to be accessible on the port 443.

Can someone please advise what am I doing wrong ?