I can't believe it, but over 4 years later, and I am having this problem on the Galaxy Note 10+. Anyone ever find a solution? I didn't have this problem with the S10+. I was using AT&T then...Verizon now, but I have the carrier unlocked phone (not that I think any of that _should_ matter).
I have a Galaxy Note 9 and was having the same issue. Here's what I found on mine.
Two phone applications were on my device.
- one that is part of the Verizon suite that I cannot uninstall and has no real information on it other than a version number (version 10.1.02.35 if anyone is interested).
- the other was an app called 'True Phone Dialer & Contacts'. I had installed it because I was having problems with the contacts manager that came with the phone.
When I installed the True Phone app, it became the default for phone calls. From that point on, I had the same issues. If in a call, I could not switch to another app no matter what I did.
I eventually uninstalled the True Phone app and that problem went away. With the factory phone app, I can switch back and forth from the phone app to other apps mid call.
Not sure if that will help anyone, but it's what I found on my Samsung Galaxy Note 9 on Verizon.
Hope it helps.
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