Voicemail Greeting always going to Default

I always had a custom Greeting for my voicemail.  Recently my iPhone 8 was updated with ios 13.5.1.  Seems that after that update voicemail is always going to default greeting.  I followed Cricket's instructions of resetting PIN and then recording a custom greeting.  Voicemail still goes to default greeting.  Tried to change message on iPhone itself, changed selection from Default to Custom.  Recorded a custom greeting.  But voicemail still goes to default message.  Web search says Apple problem, other say carrier problem.  Any one have a solution??