I have two SmartSolar MPPT 100/50 controllers and am using a fairly new Samsung 22 Ultra smart phone. I have connected via Bluetooth before and even changed parameters and updated firmware about 4-months ago. I have had frequent issues with one or both disappearing. I have re-booted the phone and unpaired both To revive, I disconnect the controller from both battery and solar to restore, but it's a PITA. I feel like I'm missing something - thoughts?