Game slow down on iOS

ThaiDanh

Hi, so recently I have been noticing that when in a fight and any type of notification or alarm would happen the game would significantly slow down or even freeze until the notification is gone. I am currently playing on an iPhone 8+ on iOS 13.1.2. I have already tried reinstalling. The game is just chugging when any type of alarm happens.

Edit: I tried other games to see if this occurs and MPQ happens to be the only game that would be unplayable when a notification happens.