The 2 Screens not always working

I dropped my phone

The front screen didn't work, but the inside screen worked. I used the tap and massage the phone technique. The outside sceen now works, but the inside screen doesn't work. If I partially open it, I can get the screen to work intermittently. But once it's about halfway open the screen doesn't respond. I opened the phone to see if reconnecting the ribbon cables would work, or if I could find anything loose. I tried clearing the cache in safe mode. I've tried taping and massaging it more, no difference.

Is there a board or cable that I can replace, that might be a likely culprit? Is there a diagnostic software I could use to find the faulty part? Or any other ideas?

Thanks Dan Mayer