How can I block texts from a contact using a "shortcode" name?
I've been receiving spam texts from a shortcode rather than a regular mobile number; i.e. the text message shows "FRANLOCAL" instead of a number.
I've tried Messages>Text Message>Click on contact>Info>Block this caller
It appears to work but if I check the contact again it's not showing as blocked. It's not showing in the list of blocked contacts in Settings either.
I tried adding this shortcode number as a contact and going to Settings>Messages>Blocked Contacts>Add New... but the spammy contact is greyed out and I can't add it.
(I've also reported it to my mobile network by forwarding it to 7726 but that hasn't helped.)
I'm based in the UK and running iOS 15.5.
Any suggestions on how to block this type of spammer?
iPhone 13 Mini