iPhone X freezes after iOS 12.2 update

Hi,

since I updated to iOS 12.2 then 12.3 my phone keeps freezing, eg when there’s an incoming call I cant answer or it rings I hear it but wont show on the screen that theres an incoming call then sends a missed call msg. It remains like that sometimes for 2hrs or longer during that period I cant do anything unless if the battery dies, this is really frustrating me. I thought the problem would go away when I updated to iOS12.3 but I still have the same problem.