Very strange config for server. In section Interface you must write "Listen port = " and this UDP port forward on main router. On Peer section you dont need take endpoint port, it may be randomly. Then AllowedIP 0.0.0.0/0 - you allready include all others IPs.
Also can you please post config of client without sensetive information.
WireGuard is a stateless technology, even if you see server work, it doesent mean anywhere.
The Wireguard client Listen Port is automatic. A random Listen port is generated after it is being set to Active Status. Are you suggesting to provide a static value ?
UDP port forward on main router.
I’ve configured the main router to have UDP port forward on the internal host ip of my GL-MT600 with 51820 as the internal port number.
I’ve also tried to delete and add back again the wireguard client profile just to make certain that the keys in the configuration file are correct. Likewise, restarted the wireguard server multiple times.
Could you be able to recommend other steps to check and fix this issue?