You should ask him to provide you an image that can actually be read. An image that small means he made it that way for a reason before sending it to you so it tells me he is hiding something.

An iPhone can take better screenshots than that.

Your address shows you successfully received the 0.4 BTC from him but that is it. 0.75 was not sent previously.

https://blockchain.info/address/1PYmyVML85i3d2gwjiHx4sPYyzW8XtgKmf