FC 26 Clubs – FPS drop after first match + random disconnect

I only play FC 26 Clubs. After launching, the first match runs fine. From the second match onward my FPS drops heavily (stutter and input lag) and the game is unplayable until I restart. Sometimes I also get kicked with an error saying “connection to the game.” All other games work normally, and FC 25 ran perfectly on this same PC. Steps: launch FC 26, play one Clubs match (OK), start the next match (FPS drop or disconnect). Any known fixes or workarounds?