Did not fuction in the intended app

I wanted a keyboard with numbers displayed in an app that is mainly used to type license plates and addresses. This requires a lot of changing between keyboards. This keyboard when used in that app typed neither letters or numbers. When I switched back to the regular Apple keyboard that worked fine. So this app was useless for the intended purpose. It did work in other applications where it isnt actually needed.

J. J. Jr. about 123QWERTY: Customize Alphanumeric Keyboard Keys