Can't start portal maps.

Hi.  I've made a rotation of some maps with the portal website but I can't start any of them.  It gets 12 bots and then adds me and stops there.  The game mode needs 20 players but it's stuck at 13 and I can't play it.

I don't want to play online/PvP - I just want to play the game with bots, like I did with BF2042.

Can this be fixed please, because without it I simply can't play the game!

I'm on PS5.

Thanks :)