I noticed my TP-Link MR3220 3G/WiFi Router port forwarding will only work when I use the WAN port and not the 3G connection (modem).
Technically the router offers an option to use the internet from 3G, WAN or both (given a priority). In my case I am only using in 3G and apparently, the router features such as Remote management and port forwarding don't work on this interface.
Anybody can confirm that? Is there any workaround (static routing ou somethig)?