Error #4004 ! Si le problème persiste, veuillez quitter cette table et en recréer une nouvelle / If the problem keeps happening, please leave this table and recreate a new one

Hello,
when this kind of error appears, this is usually a known problem, but the conditions aren't well known, so it's always necessary to provide as much information about the game as possible, rather than just pasting the error with no context. So, things like complete position, properties of both players, or any other general information you think could help. Using F9, you could also send a game history and report the error that way with the full game.
By the way, it is also not necessary to create 2 topics which say the same thing.

I have had this issue before. It is a bug where wennever bots land on someone’s property and Hass to sell houses, sometimes a bug will occur where you need to sell one house at a time. This can happen to humans too, but bots do not realize this, so the game just glitches out. I’ve only had it once, but I have a fix. To fix this error, you must replace the bots in question with a player that has gone bankrupt or is spectating. Then they will have to trade with you for money, and you will have to except that money so that way there are restored to positive cash.