Can call a certain number but can’t send messages to it

I’m able to call this number without any problems but any text messages never go through. I had the iPhone 13 and out of curiosity put my sim into another phone and the messages sent as normal. So after trying to sort my own phone out to see if I could get around it, I eventually bought a new phone assuming there was something faulty with the device rather than my sim seeing as it worked fine in the other phone I tried. I now have the 14 pro max and am still having the same problem where I can’t send messages to this specific number only. I’ve been to o2 to see about this but it is clearly more of a device issue when the sim works fine once in another phone. Has anyone got any advice as I’ve tried all the usual reset factory settings, deleted the contact etc and still no luck.