Click on Settings->Firewall Rules.
Description:VPN
Protocol:UDP
Source Address:manually selected -> Computer IP
Source Port:Empty
Target Address:manually selected -> VPN Server IP
Target Port: VPN Server Port
After saying save, you can test the rule. If you still do not have access, you may need to add the reverse of the same rule to the rule list.
For this;
Description:VPN 2
Protocol:UDP
Source Address:manually selected -> VPN Server IP
Source Port:VPN Server Port
Target Address:manually selected -> Computer IP
Target Port:Empty
Try to access it again.