I have an old Samsung flip phone with a pre-paid plan.

The voicemail is empty but when someone calls, they receive a "mailbox is full" message.

Mailbox has always worked in the past, but no it does not.

I have seen another post where the question was whether or not call forwarding was active.  I do not believe I have that feature on my phone.

When I push *73 on my phone the options are: 2-sec pause, wait, new txt msg,new picture msg, and new voice msg - no call forwarding.

Any suggestions?