I have saved the armor items in the structure block so that when someone enters the PvP lobby, the armor items will spawn directly above the player by command, but unfortunately the items become invisible and are only visible when you click on the bottom.

this bug was fixed in 1.17.32 and added back in 1.17.34

still not fixed in 1.17.40(thx)

still not fixed in 1.17.41(thx)

and still not fixed in 1.18.0(thx)

look video for more information.