phone message is full in airplane mode

Honestly, that sounds like a carrier issue. If your phone is in Airplane Mode, cellular calls aren't reaching it at all and any error messages are being generated by the carrier's switch.

You might want to consider logging into your voicemail the old-fashioned way (on my carrier, you dial *86 and send. Yours may be different) and see if there are voicemails in the deleted section. Also, on the iPhone, go to Phone>Voicemail>Deleted and delete anything hanging around there. That may prompt the deletion of things on the server.

If all that fails, contact your carrier for assistance.

mar46 wrote:

Idris,

Thank you very much for your suggestions. I found a bunch of saved messages, by logging in to my Verizon voicemail account, and once they were deleted, the problem went away. Thanks again.

I'm so glad to hear that! Especially as it was the only idea I had.

The outgoing message is that your Voice Mailbox is full. This has nothing to do with text messages. Phone calls don’t go to the Messages app. The voice mailbox is on the carrier’s voicemail server, and has a limited capacity, typically 40 messages. That includes messages that you have listened to, ones you haven’t and ones you have deleted but not cleared from the deleted voicemail folder.