Apple id sign in requested
I have an IPad I haven't used in a long time and just turned it on -- works great. A popup on my IPhone repeatedly notifies that a device is using my Apple ID to sign in. When I select "allow" a number pops up that i'm instructed put in my IPad after the passcode. Problem is that when i put in passcode the number pad disappears and I can't enter the Apple ID verification code provided. and the pop screen continues to pop up a million times. Any advice on how enter the verification code? Or how to turn off that notification? Thank you. A
iPhone 7 Plus, iOS 12