Unwished player exchange during match

[David BRESSON]

Hello,

I'm playing un FM21 since few months and I have a problem. 

During my matches, I'm suffering unwished players exchange on the field. My right midfielder constantly change is position with the central attacking midfielder (while using 4231 tikitaka). It usually happens during timeout. I constantly correct these positions, but systematically the two players change position another time. It doesn't help me win my matchs (and it's also a little bit upsetting !). 

For exemple attached files :

My right miedfielder is ROYE, my central attacking midfielder is Pollet. Several times in match, they exchange places, and I have to correct it manually, have to wait until next time-out since they take their right places, ...

I have done something wrong, or is it a bug ?

Please help !

 

[XaW]

Have you told them to swap positions in the tactic?