Recently I have been unable to make conference calls on my S21. This is a new problem that began several weeks ago. I can successfully dial both phone numbers sequentially but when I press the Merge Calls button, I receive an error message "Unable to make conference call" and a disconnect ensues.
The device software is up to date, I have restarted the phone multiple times, I have tried several different dialers, all to no avail. Googling the problem reveals others with the same issue but I have found no solutions.
Does anyone have any idea how to fix this?
Thanks.