Why are my photos not being received?

[AC Question]

Lately i've been trying to send photos to my friend who has an i phone. I was able to send them before just fine, but lately, hes been telling me that he hasn't received any photos. On my phone when i try to send him a photo,it says that its been sent, but he doesn't receive anything.

 

[Tech-Newb]

What method or app did you use to transfer the photos?

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