Phone laggy after last update

My iPhone 11 ProMax has been super slow and I have had to press the screen harder since last update. Sometimes the typing lags behind and then sometimes I have to perform the same function more than once to get it to work. For example I received a phone call a little while ago and I had to swipe 3 times before it answered. I have to put super hard pressure to get the keys/function to work. I have powered it off and on and ran the battery completely dead. I contacted Apple and they said that there wasn’t anything wrong and that I need to go to a store. Has anyone else had this issue since the update? If so what can be done about it?