There are certain numbers which I am unable to send text (SMS) messages to. They are not premium numbers, but provide services (e.g. to check credit card account balances).
Messaging to most numbers work, but I’ve now two service numbers which I just get ‘Message Send Failure’ and a ‘Not Delivered’ notice when I try and text the service.
I have checked and enabled premium numbers just in case, but this seems to make no difference. Can anyone help?