Controller Forced to Keyboard in Rivals

Whenever I enter Rivals mode, my controller becomes unresponsive. As a result, I am forced to continue the match using keyboard and mouse.

This problem only occurs in the Rivals mode; in other modes, my controller works perfectly fine. I have already tried basic troubleshooting steps such as reconnecting the controller, updating drivers, and restarting the game, but the issue persists. Does anyone have a solution?