why doesn't my android phone connect to the amp blue tooth?

When i try to play a track to my Code 25 using gatway on my motorola droid turbo 2 running android 6.0 the search window opens but remains blank other then the ok and cancel buttons at the bottom. Please help. thanks!

I updated the gateway app 5 minutes ago to latest version - my phone is an moto g (gen2) running android 5.0.2. The app worked sort of ok on previous version but now its giving a message as follows.

      "Screen not supported - tThe minimum screen size is 640x960" 

From what I can see under the message though looks to me ok I can see "00 EL34 Heaven" and all the initial presets not covered by the message but thats it nothing works so I guess thats it after about 2 and a half weeks of being apple to control from the app I now find that I cannot do anything from the app.

Any ideas what I need to do next.