The issue is, The phone freezes and it makes your number as not reachable, since the mobile loses the signal
and freezes up
You must have set to divert calls to Voice mail
, if not reachable..So immediately after the phone freezing up, your calls are diverted to voice mail..
These are all the issues, faced by every user
who uses the Samsung
c417, You can read the review from the following link below
The only solution is updating the phone firmware, The new firmware must be made to remove this known issues..
Try updating the firmware, would solve your issues.
Please leave me comment, if you need furthur assistance