Apparently, upon joining ideas vault there is a chance you will get into a server that had duped locked items dropped into the floor, therefore locking out your inventory completely. This makes you unable to finish day 4 and day 5 tasks, as the dev hat and a lab coat appear on your inventory. Could be probably solved by making them appear straight on you?
EDIT: IM SORRY I MEANT TO PUBLISH IT ON BEDROCK EDITION, ITS A BEDROCK EDITION ISSUE. NOT JAVA.
Closing the report for this reason, this is a bedrock issue, not Java.