Failed to connect to map server is a message you also can get while changing maps and entering portals in the game. It's usually nothing severe either, and as worst, your character might be stuck in that map until there's a reset of the map server process. Another issue similar to this can be if you get the loading screen after choosing a character, but it never loads. Most of the time it should be followed by this "failed to connect" message. If you try to choose another character that isn't placed in the same map, it sometimes let you play since every map in the game, has it's own server process. Sometimes the server needs to be restarted in order to fetch some stuck characters. If you had characters that's been stuck for weeks, you should contact the staff.
Other then the obivous reset home for your character to get them "unstuck" and trying again, make sure all the OTHER FH maps are working fine for you as well. Your best bet might be to uninstall and reinstall the whole feral heart city map itself(including the cinema map). Hope this helped a little <3
Another solution that seems to work alright (once you get your characters unstuck and whatnot as mentioned above,) is simply just waiting. Sometimes it'll let you in if you try again like, let's say 5 minutes later or something. Worth a shot anyway, right??