You cannot have a player step on a pressure plate to remove their tags. They must be OP for tags to be removed, even if a command block does it for them. This is the command:
/execute @p ~~~ tag @s remove TAGNAME
This doesn't make sense, considering they can be executed and enchanted while not being OP.
This is the command that works:
/enchant @p unbreaking 3
Thank you for your report!
We're actually already tracking this issue at MCPE-75570, so I will resolve and link this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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