There is a problem on a Realm I'm part of where chunks keep rolling back anywhere between half an hour and an hour.

This results in anything created by players in that chunk being wiped and the chunk reset by half an hour/an hour of progress.

This occurs even when a player is still logged into the Realm and they have simply moved far enough away for chunks to de-load and when they return, the chunks have reset. This also happens when players log off and log back in to find chunks reset.