I have a Pixel 6A on T-Mobile. I keep 5G turned off because it's usually slower and flakier than LTE, visibly chews through the battery (a percentage point every couple of minutes), and heats up the phone.
Are you running the latest Android release on it? I had a Pixel 6 Pro on T-Mo and experienced almost identical issues until I updated it some months ago
Turns out Google pushed the 6 series out before the OS was "ready" and "forgot" to tell anyone
Turns out Google pushed the 6 series out before the OS was "ready" and "forgot" to tell anyone