Fix javascript errors on my product page on shopify

I need some help fixing javascript errors on my product page. I asked shopify AI and it said there are some bugs. I think I may have adjusted the coding myself a while ago and I'm not sure what I did so I would really like it to be checked.

See attached errors that shopify AI found but I would like this to be checked generally as well in case this is wrong or if there is anything else. This is just a guideline.

I just made an older theme live which was last edited on 2nd June as my sales have been falling a lot the last week (since 3rd June) and it is our high season, being a swimwear brand, so this is very unusual, so I wanted to revert to a slightly older theme which was saved before sales dropped.

It would be great if this 2nd June theme (now live) could be reviewed and compared to the other theme to see if any changes were made causing these issues, or if they are actually on both themes