Wireguard no handshake

[TomNick]

Hello everybody,
I am trying to connect to my dedicated server via Wireguard and I am not able to get a handshake.

My setup:

Server       IP xx.xx.xx.147
Additional IP  xx.xx.xx.146

pfsense 272, WAN set to the additional IP xx.xx.xx.146 installed on proxmox

Wireguard setup:

Server
IP Address 10.0.0.1/24
Listen Port 51820
Private Key AL+8kOD7oQcVfETxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Public Key 38FTdVQH8zaYj3Jxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

[Interface]
Address = 10.0.0.1/24
ListenPort = 51820
PrivateKey = AL+8kOD7oQcVfET5501exxxxxxxxxxxxxxxxxxxxxxxxxx

[Peer]
PublicKey = +0AC5NFY61TkyVZibVxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
AllowedIPs = 10.0.0.2/32

Client
IP Address 10.0.0.2/24
Listen Port 51820
Private Key WF+FZ6gmhloJ0i1J5qTaKguV8asxxxxxxxxxxxxxxxxxxxx
Public Key +0AC5NFY61Txxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

[Interface]
Address = 10.0.0.2/24
ListenPort = 51820
PrivateKey = WF+FZ6gmhloJ0i1J5qTaKxxxxxxxxxxxxxxxxxxxxxxxxxxxx


[Peer]
PublicKey = 38FTdVQH8zaYj3JM1uX+bDG0xxxxxxxxxxxxxxxxxxxxxxx
AllowedIPs = 192.168.21.0/24
Endpoint = xx.xx.xx.146:51820

My FW WAN rules:

Action
:
Pass

Interface
:
WAN

Protocol
:
UDP

Source
:
any

Destination
:
WAN Address

Destination Port Range
:
(other), 51820

Description
:
Pass traffic to WireGuard

My FW rules Wire Guard:

Use the following settings:

Action
:
Pass

Interface
:
WireGuard

Protocol
:
Any

Source
:
any

Destination
:
any

Description
:
Pass VPN traffic from WireGuard peers

Does anybody have any idea what could be wrong? Thanks for some hints