File Upload feature messing up page formatting

Hello - I’m having trouble using the File Upload feature on this page. I’ve built out a custom menu/nav that stays static on the left hand side of the page. In a shorter viewport height (13" screen etc…) I’m running into an issue where the nav bar/menu on the left will scroll up and down ONLY when the file upload button is set to display.

You can replicate my issue by shrinking your view port height, and toggling display/display:none with the file upload button.

Has anyone run into this issue? Any help solving it would be greatly appreciated!!

Here is my site Read-Only: (Webflow - MMMco)