Is the WAN of your server router public IP (dynamics is also ok, as long as it is not CGNAT), or if the server router connected to the primary router, is the primary router configured the port forwarding?
When you use WG APP in iPhone and MAC to test connecting to WG server, are they connected to other networks? like try using iPhone's mobile cellular to test (it can't connect directly to the server router's LAN/WLAN)
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