When to unmatch someone?

Please only comment if you’re telling me how much longer you’d wait for their response before removing

My last message from them was 18 nov. they read my message on 19 nov and one I sent 3 dec asking if everything was ok a week or so after I sent the recent one. Still haven’t heard back. How much longer would you wait before removing them? Their last message said they were looking forward to my response so idk

We were talking a few times week to once a week. They’re in Europe so they don’t celebrate thanksgiving either. It’s just weird they suddenly disappeared