Faced a similar bug to Martin today, wasnt in a party but the party menu said I was. I couldn't leave the party. As far as I know i wasn't in a party with any of these guys. I tried to CC (as advised from https://royals.ms/forum/threads/party-bug.88764/) but the HP bars were still showing on the side. Relogging solved the issue!
for hp bar, u can just create a new party n disable n re enable ur hp mark. u will see that on re enabling it, there is just u. the impt thing to resolve is all the names in party tab. else u will be stuck with the party bug
