Hey, this is a known bug. The Composer 2 model selection doesn’t persist and resets to Composer 2 Fast when you open a new chat. Others are seeing the same issue too: Model reverts to composer-2-fast on each new chat
The team is aware and tracking it.
For now, the only workaround is to manually re-select Composer 2 in each new chat. Not ideal, but your existing chats should keep the correct model.