Keyboard Keeps Disappearing

I’ve noticed other posts with no resolution. My on-screen keyboard randomly fails to appear. This is application independent. It happens in all apps, to include when I swipe down to search installed apps. I am on an IPhone 7 Plus running the latest IOS version. This has occurred throughout the past several IOS versions. The only fix is to get out of whichever app I am in and restart. Not that while the keyboard fails to appear, the screen still acts as if the keyboard is present….press where the keys should be and characters appear. I have noticed this also happen in the IPhone 11 and on IPads.