Board Thread:ROBLOX help and discussion/@comment-32459527-20170702160356/@comment-24411369-20170702174423

You should describe it more specific. Are you talking about a gamepass or a gear?

Gamepass:

After you bought the gamepass, go to a new server. If you went to the same server after you bought the gamepass, it won't work.

Gear:

Look at the "Gear Types allowed" section on the game's description. I assume it's a musical instrument. If it allows that gear type, then the boombox will show up in your game.