Doesn’t change image size properly.

This is the only program that doesn’t change image size properly. Now I admit I don’t know much about this stuff but with every other program I’ve used, I choose to change the size and it increases it well with little noticeable quality loss, like pixelmatr. With Affinity photo I change the document size and which ever picture I use gets pixelated/checkered. I do the same thing choosing the same numbers in pixelmator and it does it fine. Something is clearly wrong with the Affinity. If it’s something I’m doing wrong then it shouldn’t be harder than what I’m doing. No other app I’ve tried has this problem.

DomDomDomDom about Affinity Photo, v1.4.1