Accordion menu not expanding

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Over the last half year or so we have been using an accordion menu on our product page, which was workng fine up until recently after making some minor edits in Weglot (translation app).
We have really done our best to locate the problem in the HTML but we couldn't find a solution and don't know what is wrong with the code or script that is making the accordion menu unable to work properly. 

We would like to make the accordion menu expandable again, but we don't know how to fix it.

This is the product page I'm referring to. 

If you need additional information, feel free to ask. 
Thanks in advance to those who are trying to help us!