[Solved] Why wont the game detect a gamepass purchase?

I just added a gamepass to my game, and my script that detects whether you own it or not works fine in studio, but when I tested the game on Roblox it wouldn't work. Is this just a glitch or did I do something wrong?

local MarketPlaceService = game:GetService("MarketplaceService")
function CheckforPass(userid)
    if MarketPlaceService:UserOwnsGamePassAsync(userid, 5377879) then
        return true
    else
        return false
    end
end
if CheckforPass(game.Players:GetUserIdFromNameAsync(script.Parent.Name)) == true then
    print(script.Parent.Name, " owns the Advanced Defuser Gamepass")    script.Parent.Humanoid.WalkSpeed = 45

end