You know the bug that items disappearing from item frames, it happened to me , i have a wall of 5 times 3*3 area of Nautila shells with heart of the sea in middle, and a floor of Armour stands with all Armour sets available in minecraft, complete sets of  a gold , a iron, 3 leather, a chain mail and a diamond Armour displayed a t my base and my fully enchanted diamond sword in item frame, as our server updated the above items disappeared, i tried complaining to admins but ultimately you are my only choice, i will be waiting for your reply, Thank you