Can no longer add apps to my ipad dock!!

How many apps do you have in the dock? I think the limit is 10 and that would include recently used apps. If you have recently used apps enabled, that would allow for 7 apps in the dock.

If you are meeting those requirements, try restarting the iPad and see if that fixes it. If not, try a forced restart. To force restart your device, press and hold both the Sleep/Wake and Home buttons for at least ten seconds, until you see the Apple logo.

I know this sounds stupid, but have you tried moving apps off of one of the screens to another screen or move to another home screen and see if you can add an app to the dock from that screen?

I know that some users were having issues with the dock moving out of place in iOS 11.xx. ( can’t remember exactly which version it was) and I wonder if this is related.

Interesting. I can drop an app anywhere on the dock to add it. Also, I gave you bad information on the number of apps in the dock. I just dragged in two more and now have 9 in my dock plus the three recent apps on the side.