Menu Editor- Not able to save the position changes!! - 502 Bad Gateway

Try to change position for the dropdown item from the menu, but experience 502 bad gateway when I clicked save.

Start by reproducing the failure in the Admin Menu Editor: move a dropdown item and click Save. The payload names no files or tests, so trace the save request and identify why it returns 502; done means position changes save successfully without the gateway error.

Written by the indexing model from the issue text.