Dropdown Menu Anomaly

On my Wix website surrey hants wildlife com my dropdown menus all work perfectly in preview, but each time I publish changes to my site, certain topics in some dropdown menu’s are missing. Weirdly if I click certain adjacent dropdown menu’s on my site and then go back to the faulty menu they reappear and the previously missing topics all function correctly, however if I then click on another different dropdown menu, and return to the original faulty one the same fixed topics are now missing again.
There appear to be two affected dropdown menus out of 21 which display this fault, I have also noticed that these two faulty dropdown menus always show a duplicated topic at the foot of each of these two multi-topic menus (In the attached Screenshot images, image 1 shows the correct display, the topic Hawfinch is visible 5th topic from top, but in Screenshot image 2 Hawfinch is now missing and Sedge Warbler at the bottom of this dropdown is now shown twice, also in menu “Birds 4” the bird Coot at the bottom of this menu is also shown duplicated twice as shown in Screenshot image 3.
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Any clues as to what’s going on?
Kind Regards
Mike Deegan