Sometimes the graphs load, sometimes they error

I have a couple of charts on a page. Like the subject says, sometimes they load perfectly, and other times, they return the error "Cannot read properties of undefined (reading 'length')." The content of these charts is rendered with query results, so I took the rendered code from a time when it worked and the code from a time when it didn't and ran it through text-compare.com. It's the exact same code.

I've systematically stripped out every other .js file to see if it's a matter of incompatibility, except for Bootstrap 5.3.2 and Popper 1.12.9 which the site really needs. Have any of you encountered this issue?