Argument 1 missing or nil,help?

I was trying to print the names of the models in my set that I have but I keep getting a error saying:

17:33:39.508 - Argument 1 missing or nil 17:33:39.509 - Script 'InsertService = game:GetService("InsertService") UserSets =', Line 4 17:33:39.510 - Stack End

I'm pretty sure I put something in argument 1,I don't get why its saying this.

InsertService = game:GetService("InsertService")
UserSets = InsertService:GetUserSets(1077607,1)
SetId= UserSets.AssetSetId
Collection = InsertService:GetCollection(SetId)
for i = 1,10 do
Model = Collection[i]
AssestId = Model.AssestId
print(Model.Name)
end

It would be that SetId is not returning as you expect it to for some reason, you should check into that.