Huge error – when scrolled, dropdown menu is vertical banner w/ strange chars

Hi, I have a very urgent and strange issue on my live site.

When on any page, if at the top of the page, and you hover over the main menu to show the sub dropdown menu, it works perfectly. If however, you are scrolled to any other section of any page on the site, the drop-down menu doesn’t show, instead it is a very thin vertical banner on the left-hand side, filled with strange characters. I can send a screenshot.

I have gone onto the staging site and reset the css caching in the max menu settings, and then gone through and disabled plugins to see if it’s being caused by a clash. Nothing is fixing the issue.

Please advise, thanks,

Lucy

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