Lost items in Chest on Realms after upgrading to .17

I had my Netherite tools in a chest.  I hadn't played in a few weeks on Realms.  I logged into my Realms account and (after paying the fee for another month) I was able to access my Realm.  However, I could not locate my chest with my Netherite pickaxes / shovels (I have screen shots of them from before 1.17) and have found several other Chests that were full that are now empty.  When I downloaded a copy to my local computer, I experienced the Nether reset bug.  I downloaded another copy from Realms to my local computer and the Nether reset but did not occur.  I have searched all my chests and I have found 2 chests that used to be full and are not empty that I know of, and my Netherite tools (which I had placed in a chest as they were fully mended while I xp grinded to mend my other items) were no longer in game.  Can you identify if this is a bug, or if my Realms game file got corrupted somehow?