The option itself may exist, but new codes haven't been added for Phantom Forces in Roblox for a long time. As of this writing, there are no available codes to redeem within Phantom Forces and players ...

Developer StyLiS Studios created Roblox Phantom Forces on August 31, 2015. It was first made available for purchase in September 2015, and on December 8, 2016, the first full release made it available ...