Players switch positions at kickoff despite correct custom tactics

I’m experiencing a bug in Ultimate Team when editing my tactics through Team Management.

Whenever I change the position of a player by swapping them with another player, the changes appear correctly while I’m editing the tactic. However, after I save the tactic, the position changes are not actually saved.

When I leave Team Management and return to the tactic, the players have reverted to their original positions. This happens consistently, regardless of which players I move or which positions I change.

Steps to reproduce:

1. Go to Ultimate Team → Team Management → Tactics.
2. Select any tactic and edit the formation/positions.
3. Swap the positions of two players.
4. Save the tactic.
5. Exit and return to the same tactic.
6. The players have returned to their previous positions.

Temporary workaround:
I have tried saving the tactic again and exiting/re-entering Team Management, but the position changes still revert to the original positions. At the moment, I have not found a reliable workaround that makes the changes persist.

Please investigate this issue, as it prevents me from properly saving and using custom tactics.