Photography

First and foremost, im no expert, maybe not even a novice at this point, so theres definitely a possibility that the issue is on my end.

I bought a lens from KEH. A Canon 17-55 f/2.8 IS USM for use on my Canon EOS RP (with Canon RF-EF adapter). Needed something wide for a large family portrait, but also needed Image Stabilization, because the body has none built in, so that narrowed down my options quite a bit. I found this lens for a super reasonable price, like half of what Canon wants for them, so jumped at the opportunity. I recieve it, and right off the bat, it has issues focusing. In the viewfinder the subject will be in focus, but the actual photo is completely out of focus. I immediately sent an email to KEH, and they responded the same day with a paid return label, and offer for a replacement.

A little over a week later, I have a different lens, and it's got issues too, seems to even be the same issues, but not entirely sure. I will attach a link to a part of the picture.

My main question is, is there some compatibility issue that I am not aware of between certain lenses and the adapter/RP, or are these lenses actually damaged?

Full disclosure, KEH has been really responsive, and has already sent a return label for the second lens, but I really need to make sure I'm not doing something stupid to cause this issue myself.

Pic: https://imgur.com/a/zzcbiIO