Constant signal loss with my S21 Ultra with Android 12 purchased in mid 2021. New transmitters lasted only weeks or days. Dexcom is aware of the problem. Rather than quit, I unpacked my old backup LG android phone. It has android 8.0 and runs the program perfectly using only bluetooth. I have to carry 2 phones but gain the peace of mind that was promised by Dexcom's marketing. Hope Dexcom figures it out soon.