I had problems with voicemail that ended up going to tech support. All has been well since. No changes have been made to anything but I noticed that a couple of calls that had come through to me didn't trip to voicemail - and they did ring for a long time.
So I dial 222 and check, it says I have no messages. I record a personal greeting, and it's accepted it - I just used the default one before. All seems fine.
Today again, I get a call, but it doesn't trip through to voicemail.