It's a bit of a long story so I'll just give the pertinent information.
Last fall a client bought me a cellphone as he knew I had lost mine. He had already opened it and had bought and inserted the SIM card and then gave it to me as an "early Christmas present". I've known him for a long time and always trusted him so had no reason to think anything weird of it.
But, shortly afterwards I realized that he was the one person I could not text. When I would try to text him, nothing would happen. Not even a failed message text. Just nothing. This went on for a couple of weeks - he could text me but I could not respond. Then one day it returned to normal. He said it was because his number was in my contacts and for some reason it was screwing up. But I recall I had other numbers in my contacts and did not have a problem texting them.
I no longer have the phone and there is a bit more to the story now but I just want to know what you guys think. I want to trust that he has been truthful but there have been some issues and this one in particular keeps nagging at me even though it happened a while ago.