Hello @nef,
What version of OJS is the journal running on?
This post outlines a similar issue encountered by a user: [OJS 3.2.0-3] Section ordering glitch, please help - #2 by UBWolf - not sure if that’s the issue that you are encountering exactly, but it may be worth taking a look.
Additionally, if you are running 3.1, there has been a reported issue on this, related to QuickSubmit plugin (which has been addressed). This is outlined here: Order sections in issue ojs 3.1.1.0 - #7 by lucaslmdr
-Roger
PKP