A hand holding bug

Hello bugs.mojang.com! I reported a bug becuase i found a bug of holding a block, actually i'm created a world and build some structures for the Halloween. Then when i was about to hold the Gray Concrete, it just bugged. The inventory bar saids that ikm holding the Gray Concrete but when i look at my player's hand... The Gray Concrete is not showing, i hope that you fix that. Thank you!