Bug / Issue - A div is displaying in my nav that isn't supposed to be there

Design help General
3

I just sent two vids to support over something that may be the same issue. Problem is, fixing things manually doesn’t solve the issue permanently. The fix lasts only a few minutes at most.

part 1:

part 2:

Share Link:
https://preview.webflow.com/preview/cpups-test?utm_medium=preview_link&utm_source=designer&utm_content=cpups-test&preview=ebe219589b5a8a20ea923aa4e7e4fe76&pageId=5fb85a0a019a29d2ed4d98b6&mode=preview