To add to your thread …
Most Samsung phone's have a diagnostic tool built into them which is accessible via the Samsung Members app, and via launching the phone's Phone App and dialing *#0*#
Check the ports for debris using a torch.
A Samsung Experience Store or Samsung Service Centre can help too.
Current Phone ~Samsung Note 20 Ultra 5G SM-N9860_256Gb SnapDragon 865+ Samsung One Ui 3.1/ Android 11.