Fragmented product image display


I’ve been experiencing problems with displaying product photos whenever I add a new product on my website (no changes happening in existing unless I add more pictures to those products…). This is only a recent problem.
I believe it might be because some products have a quality selection layout and others have a photo slider, but I’m not a designer, so I am unsure how to fix this. Every new edit the previous designer made has made the site worse than before. I am quite desperate already.
Could someone help me out?

Thank you very much!

Here is my site Read-Only: LINK
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