Friend can no longer join server

I’ve been running a server for almost a week now for me and my friend and he was disconnected while playing and hasn’t been able to join since he gets the error code$annotatedconnectexeption . I’ve tried restarting the world and the server, changing to another mod pack, disabling his firewall, and restarting his pc. I’m using if that helps, I also restarted playit tunnel and nothing. I am able to join through the playit just fine and shows that the server is up. Any help would be appreciated.