Trying to use a ScriptModule error: Attempt to call an Instance?

I have a module script inside ReplicatedStorage, when I try to require and use it as a function inside a script located in ServerScriptService I get an error saying Attempt to call an instance

My ServerScriptService file:

local GetRandomNums = RS.Utils:WaitForChild('GetRandomNums')
-- ...
 local randomNums = GetRandomNums(0, #players:GetPlayers(), 2) 

The Module itself:

function GetRandomNums(min, max, numsCount)
    -- ...
end

return GetRandomNums

How can I fix this problem?