Since I updated to Android 6.0.1 on my S6, calls drop out. How do I fix this?

[AC Question]

Since i updated to android 6.0.1 on my S6 calls drop out

Since i have updated my phone to Android 6.0.1 all of my calls just drop out, so ill be talking on the phone and they just go silent and disconnect ?!

How do i fix this