Need HELP! Why some of my picture is automatically rendered to be 78px x 78px?

Store Design
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Shawn512_0-1697117250376.png
Shawn512_0-1697117250376.png1505×951 221 KB

Shawn512_1-1697117272835.png
Shawn512_1-1697117272835.png2267×685 86.2 KB

I add pop-up size chart in product page, link to a page, than upload a 450x450 picture.

but it rerendered to be 78 x 78.

dont know why~~~

any idea please?