Hello I own a Samsung Galaxy S21 Ultra. For the past 3 months or so, I have been experiencing issues with connectivity to cellular network. Wifi works fine, but thr cellular network gets extremely unstable every 30 minutes or so. I have dual sim cards, I tried using only one but it didnt solve the issue. I am also sure the sim cards work on other phones. I have factory reset my phone & took it for maintanance at samsung's own centers. The issue persists. Any suggestions?
