I made a game back in 2020 and I have found that when I type my game up on Roblox, multiple users are copying the game (the original one is the dark blue background which is mine):
Of course! First you should submit a Roblox Support Ticket which can be found here. Select your platform, DMCA, and Owner DMCA Claim, make sure to show specifically what they stole, and what games stole the assets. Then you’ll get an email back from Roblox within a few days.