My response was a step by step solution that I found worked for connecting my Samsung Galaxy S7 to the Pokeball Plus. The comment about balance put aside, I think you misunderstood my suggestion (re: turning on Bluetooth from app). I noticed that, both with Pokemon Go plus and Pokeball Plus, if I connect to the device using my phone interface (outside the app), it will lock the device from use within Pokemon Go. In reading the OP again, having been playing the game for a few weeks, it seems they're experiencing two different issues: one that prevents them from transferring Pokemon from Go to Let's Go, and another entirely different issue preventing them from being able to use the Pokeball Plus. While this setup worked for my Galaxy S7 (which wasn't listed as a supported device), it may not work for older phones. If that's a issue you're experiencing, contact nintendo. Don't shit on someone else who's trying to help just because their solution didn't apply to yours.