Why is my ban script only kicking players and not banning them?

I am working on a ban list that is supposed to add banned players to a datastore that all servers can access. However, it is only kicking the players once and not banning them. Also, I made a ban list GUI and their name is not being entered there for the admins to see just in case they want to unban anyone. I really need help.

Script:

dataStoreService = game:GetService("DataStoreService"):GetOrderedDataStore("BanList")
banPlayer = game.ReplicatedStorage.BanPlayer
kickPlayer = game.ReplicatedStorage.KickPlayer
unbanPlayer = game.ReplicatedStorage.UnbanPlayer
listChanged = game.ReplicatedStorage.ListChanged

local function findNextAvailableKey()
	local key = 1
	while true do
		local isAvailable
		local success, notSuccess = pcall(function()
			isAvailable = dataStoreService:GetAsync(key)
		end)
		
		if notSuccess then
			warn(notSuccess)
		end
		key = key + 1
		if isAvailable == nil then return key end
	end
end

local function sendList()
	local list = {}
	local key = 1
	while true do
		local player
		local success, notSuccess = pcall(function()
			player = dataStoreService:GetAsync(key)
		end)
		
		if notSuccess then
			warn(notSuccess)
		end
		
		key = key + 1
		if player ~= nil then table.insert(list, game.Players:GetNameFromUserIdAsync(player)) else break end
	end
	
	listChanged:FireAllClients(list)
end

local function addToDataStore(player, plr)
	local success, notSuccess = pcall(function()
		dataStoreService:SetAsync(findNextAvailableKey(), plr.UserId)
	end)
	
	if notSuccess then
		warn(notSuccess)
	end
	
	sendList()
	return "Added"
end

local function checkIfInList(player)
	local key = 1
	while true do
		local isThere
		local success, notSuccess = pcall(function()
			isThere = dataStoreService:GetAsync(key)
		end)
		
		if notSuccess then
			warn(notSuccess)
		end
		
		key = key + 1
		if isThere == player.UserId then return true end
		if isThere == nil then return false end
	end
end

local function accumulate()
	local list = {}
	local nilCount = 0
	local key = 1
	while true do
		local value
		local success, notSuccess = pcall(function()
			value = dataStoreService:GetAsync(key)
		end)
		
		if notSuccess then
			warn(notSuccess)
		end
		
		if value == nil then 
			nilCount = nilCount + 1 
		else
			table.insert(list, value)
		end
		
		if nilCount >= 2 then break end
	end
	
	return list
end

local function reorderData()
	local data = accumulate()
	local key = 1
	for _, value in pairs(data) do
		local success, notSuccess = pcall(function()
			dataStoreService:SetAsync(key, value)
		end)
		
		if notSuccess then
			warn(notSuccess)
		end
		key = key + 1
	end
end

local function removePlayer(player, ID)
	local key = 1
	
	while true do
		local success, notSuccess = pcall(function()
			local player = dataStoreService:GetAsync(key)
		end)
		
		if notSuccess then
			warn(notSuccess)
		end
		if player == ID then
			local success, notSuccess = pcall(function()
				dataStoreService:RemoveAsync(key)
			end)
			
			if notSuccess then
				warn(notSuccess)
			end
		end
		key = key + 1
	end
	
	reorderData()
	sendList()
	
	return 0
end

game.Players.PlayerAdded:Connect(function(player)
	if checkIfInList(player) then
		kickPlayer:Fire(player)
	end
	
	sendList()
end)

banPlayer.OnServerInvoke = addToDataStore
unbanPlayer.OnServerInvoke = removePlayer