I suddenly cannot send texts to one contact,although I can receive texts from this contact and we can phone each other. I have an iPhone SE and they have a basic Samsung phone and text device. Though this suggests the Samsung has somehow blocked my number their local O2 shop has apparently checked the phone and says there's nothing wrong with it, and of course the phone part still works both ways. I had a 5c when this first happened but have since upgraded to an SE and the problem is still there, so assume it isn't me. Any suggestions as this is getting very frustrating.
