I have 4 systems and have been using one parent system to aggregate all of the systems.

It was working fine until 23/nov/2022 at 11:20 am. Now, when I go to any child system, the Parent System is set as “None”.

And even if I change the Parent System and click Save it won’t save.

If I go to the settings of that child system again, the Parent System still as “None”.
Any ideas to help me out?