If you have already confirmed with the recipient that their address is supposed to be: 3E7XkASFsXKKbh79yupoU8bMRTffByhJr9
Then those coins were definitely sent and
confirmed... the blockchain doesn't lie!
The issue is at the recipient's end with their "wallet". Do you know if they were receiving coins to their own personal wallet? or if it was being sent to an exchange, website or web wallet of some kind?
that will be an interesting follow-up question. but more then likely, the receiver already spent that money. because if you will look at the address as provided by the receiver (it seems that after receiving the btc, he sent it to another address). i dont think the receiver was being honest here. just my impression.
unless, he is using a fraudulent web wallet (which possibly he has no idea) and the owner of that site already sent it to their btc address. [but then again, not your fault]
https://www.blockchain.com/btc/address/3E7XkASFsXKKbh79yupoU8bMRTffByhJr9@OP, you have proof that your tx went thru. as HCP said, "the blockchain doesn't lie"
hopefully the OP didnt send any of his identification cards as it is really not necessary. high likely that the receiver is lying for whatever reason.