9 players from the beginning

I start with 11 players but as soon as the match starts my 2 forwards leave the field and I’m playing with 9 players instead of 11. If I move the 2 forwards that I started with that now are gone to the midfield they would come from the bench removing from the field my 2 midfielders so I play with 9 players as well. So annoying. How can I fix this bug