Can't connect to other areas from town

Every time I enter the game, then try to go to hideout, I get disconnected and receive the message "could not connect to instance"

Can you go anywhere else besides your hideout? Different act waypoints, other people's hideouts, etc?

If so, either your hideout crashed and you need to either wait out the instance reset or force it with Helena changing to a different hideout and back to your hideout.

If you get that error going elsewhere too, then you may have any number of issues and may get better help in technical support. Could be anything from corrupted files, third-party interference, network routing, general ISP issues, etc.