Trying to show online staff members

Hello, I have this code where I am trying to print on chat a list of all online staff members:

RegisterCommand('staff', function(source)
	local catistaff = 0
    local staff = vRP.getOnlineAdmins{};
    for k,v in pairs(staff) do
        local player = vRP.getUserSource{v}
        local name = GetPlayerName(player) or "Unknown"
		if name ~= "Unknown" then
        	TriggerClientEvent('chatMessage', player, '^5' .. name .. ' ^0(^5' .. v .. '^0) -> ^1' .. vRP.getUserAdminTitle{v})
			catistaff = catistaff +1
    TriggerClientEvent('chatMessage', source, 'Staff Online: ^1' .. catistaff)

When I use the command [/staff] in game I get this error:

[    c-scripting-core] InvokeNative: execution failed: Argument at index 1 was null.
[          script:vrp] SCRIPT ERROR: Execution of native 000000002f7a49e6 in script host failed: Argument at index 1 was null.
[          script:vrp] > [global chunk] (TriggerClientEventInternal.lua:3)
[          script:vrp] > sendStaffMessage (@vrp/modules/admin.lua:411)
[          script:vrp] > callback (@vrp/modules/admin.lua:317)
[          script:vrp] > handler (vrp-lib/Tunnel.lua:139)
[          script:vrp] null

It seems that most likely the variable player is empty.

It also seems that you’re calling the function that gets the player variable incorrectly.

It should be changed from:

local player = vRP.getUserSource{v}

To the new execution:

local player = vRP.getUserSource(v)