Can't use internet with my openvpn server as MT300N-V2 client

I have a openvpn server hosted in a ubuntu vm, if Router clients try to connect to vpn then internet services are off, this is my server conf file:

Server config

please use this command to check if there’s any route conflict.

ip route

I’m not sure if br-lan & tap0 are in conflict when having and respectively.
You can try change lan ip to