Samsung S6 - problems with calling and receiving calls

[nick6425]

95% of the time that i call someone, they can never hear me and end up hanging up. When i call right back, they can hear me alright. 

Other times it is very difficult for them to hear me, but when they call me back, neither one of us has a problem hearing the other.

Furthermore, the amount of times i have my phone turned on with the ringer on loud, and receive a call that doesn't ring on the phone. I don't see that anyone has called me until i see the phone flashing light to indicate that something new has happened that i haven't answered. I'm not being funny but all three issues are very frustrating. All software is up to date and i've tried everything barring a factory reset. 

Any suggestions?

[NFtoBC]

Assuming you are in an area with good signal strength, and the phone is not obscured from the signals, it should be very rare when you do not receive a ring signal, though it happens on rare occasion with my iPhone as well. I find it happens less frequently if I reboot my phone more often, so I have started the habit of re-starting my phone more frequently, and find fewer instances of problems.  How often do you usually restart your phone?