My Phone OLED screen broke but the physical screen has no cracks

About 2 months ago I broke my phone screen (shattered the phone completely) and I got it repaired by a really nice guy. I realised there was a problem with my fingerprint sensor after he repaired it so I went back to him and he reconnected the fingerprint sensor and gave the phone back to me for free. I also realised the screen had some minor issues like the bottom half being darker than the top but I left it.

So today I threw my phone onto my bed and it slid of the mattress and fell onto the floor. I thought fine, I've probably done this 100 times before and my phone was completely fine. The drop was about 30cm. I look at my phone and the display is completely ruined, grey, black and purple colours. There were no cracks on the phone at all or the screen protector and it also had a case. After inspecting it I realised the top corner of the screen was slightly lose and pressing it made the screen kind of return, while still glitching.

Is this my fault as I know I dropped the phone but I feel like he messed the guy messed up the repair. I also don't want to pay again if he messed up the repair. How should I go about this? I did everything he told me to like leaving the rubber bands on overnight as well.