There is nothing using a forwarding port at all. 1701 isn't in the list, and it can't be added as well. I think TPLink is using it behind the scenes, whithout telling us....

@Atlasior TPLink AC1900 EU ver 1.0. Same problem, still no solution? Maybe the vendor har set it up internally to be able to access it remotely.... First post was i aug 2020, still no solution???