I have problems receiving voice messages on my Apple iPhone 15 Plus
If you can't receive messages on your voicemail, there may be several causes of the problem.
Call 901 and follow the instructions to set up your voicemail. If you've previously deactivated your voicemail and want to reactivate it, call 1750 (free of charge when calling from your own phone).
Call 901 and follow the instructions to activate your voicemail. If you've previously deactivated your voicemail and want to reactivate it, call 1750 (free of charge when calling from your own phone).