iPhone 7 lagging when unlocking

Wondering if any iPhone 7 users have experienced this issue whereby the phone will lag and become very sluggish when unlocking the phone. This issue arrived when I updated to iOS 14 and I didn’t have this problem in iOS 13. After unlocking , the animations will turn off and opening apps, scrolling through your apps will be really really laggy. After about 10 second when the unlock icon at the top of the screen disappears, then everything run as usual. Please respond if anyone have faced this issue before.