Same issue here. I can't even use VOLTE call quality is terrible. Also phone is one one bar as I am typing.
The New Samsung Galaxy Note 10+ appears to be having a signal reception issue &frequent dropped calls. Places where I have had great network service I have non places where I drove with out interruptions now I have many. There doesn't seem to be a fix insight.
Samsung has been having this network issue since the release of the s10 and now it has resurfaced in the note 10. Most of the phones in the first dispatch tend to have this problem.
I have an AT&T branded Note 10+, I live in Las Vegas and I'm struggling with dropped calls a lot. In places my note 8 never struggled. I'm also having issue with connecting to data when I'm out and about town. Phone has been restarted along with factory reset to see if any improvements. None so far. I've checked multiple times to see if there's an update.
I heard that if a component is not attached tight enough in the Note10, there can be weak signal issues. This was from a teardown I saw somewhere.
Samsung doesn't test for proper signal connection according to what I see in the diagnostics TESTMODE.
Problems are back with mine as well. I thought switching carriers was the solution but all issues are back with cellular reception. The note 8 didn't have that great of cell service but the Note 10+ makes the note 8 look superior in reception.