Friend sent me a text, I never got it, but they got a reply I did not send

[AP802]

So in short:

My friend sent me a text

I never got it, but they got a response (that was not from me) that said "Sorry you have the wrong number".

My friend called me to see what the deal was.  I said I never got your text in the first place.

Then I sent a text to them, they replied back and we were able to text from then on. They sent a screen shot of their text to me showing the message I never got and the strange reply of "Sorry you have the wrong number".

We had no history of texts before this (it had been a few years since we last chatted).  What could possibly cause this to happen? 

[vzw_customer_support]

I'm here to help with your message concern, let's look into this. Which message application are you using? Please tell me more. 

-Yani