iPad Pro screen keyboard key fails in Diagnostics

I have problem with the screen keyboard on my 3rd generation iPad Pro (11 inch). I am trying to run Diagnosticsbut cannot as the Wi-Fi password is impossible to enter as the first (and maybe more) character is one of the keys which doesn't work. I know that if I can rotate the screen view 180 degrees then the key works. The screen view does not rotate. I have tried a bluetooth keyboard but, it seems, Diagnostics either doesn't switch bluetooth on or doesn't connect. Suggestions please.