We have a client who we just recently setup a 3CX 15.5 server for. Most everything is working as intended, however, recently there has been a problem of when using internel transferring, the phone will just continue to ring and not go to voicemail. VM is enabled on all extensions. We updated the firmware on all of the phones last night, as updating the firmware on one phone seemed to correct the issue, but after the FW upgrade, the issue still persists, even on the one extension that was working after the first upgrade. Any Ideas?