You might have a corrupted menu container due to the fact that you have not deleted the old hamburger menu (it is natively hidden) before adding the new one.
Delete the new hamburger menu, inspect the layer panel for finding the old one (must be in “don’t display” mode), delete it, then save and close the editor, empty your browser cache, reopen the editor and add the new hamburger menu.
If the issue is still there, contact the Editor X’s support.
You can create custom triggered buttons opening and closing the menu container by using the following API : https://www.wix.com/velo/reference/$w/menucontainer