I need an fps gun pack for my game

I want to put fps guns into my game like this model : https://create.roblox.com/store/asset/11096757605/Fps-gun-pack-FREE

but it keeps making errors like this
20:36:39.335 Backpack.UZI.Program_Client:1239: attempt to index nil with ‘C0’ - Client - Program_Client:1239
every single time i equip the tool
its just annoying because i know this works for real because I tried it in one of my games and it worked
please if you can fix this issue or give me a new gun pack to work with

wron link https://create.roblox.com/store/asset/12684060674?viewFromStudio=true&keyword=&searchId=d20a9ee5-7459-423f-962d-291882f05ad1