My issue is similar but for only a 10-player realm. My friend and I kept getting disconnected. When rejoining, the world had rolled back about 5-10 minutes. We noticed significant lag when going near villages and portals before being disconnected. Both of said villages had active raids. After the fourth relog attempt I tried activating the other worlds on the realm to see if it was a world-specific or realm-specific issue. Second world worked fine at first, if a little laggy. Moved on the the 3rd world. 3rd isn't lagging and i can relog and edit the world normally. 2nd however has become inaccessible now in addition to 1st. Attempting to activate them gives me OP's error message. Any attempt to edit either of the first 2 worlds only shows information for the 3rd even though the edit world title indicates otherwise. When cancelling out of the edit screens, a new dialogue box appears claiming some of the changes could not be applied. It is my understanding it shouldn't be attempting to apply changes if I cancelled out of the screen in the first place. Hopefully this doesn't indicate my worlds have been overwritten.
this is on bedrock realms for ps4, v1.18.30.
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Affects 1.20.41 playstation and realms