Facing issues with some chats where they cant accept new messages

So, this is the 2nd time this has happened. I was using a chat and it was working up until last week. Yesterday when i posted a new message, it failed to give any response and no matter what i post / ask, nothing happens. tried vai phone app as well as desktop app.

ANy tips on what to do next to fix this? I know i can start a new chat but stupid gemini doesnt fetch info from other chats and there are no means to export a given chat to get a summary of everything discussed in the chat. The chat had a lot of crucial info & I dont have means for redoing everything again.