Why is this value nil in text filtering script?

Ive set up these two functions so that when a remote event and function are triggered, certain functions happen that filter the text and give it back to the player in a text label. When I test this ingame I get the following error:

-- Error filtering message: ServerScriptService.TextFilter:27: attempt to index global 'text' (a nil value)

And here is the script in ServerScriptService:

local summary = game.ReplicatedStorage.Summary.Value
function Filter()
    local TextService = game:GetService("TextService")
    local sumname = game.ServerStorage.Summarizer.Value
    local summarizer = game.Players[sumname].UserId
    local filteredMessage = ""
    summary = game.ReplicatedStorage.Summary.Value
    success, errorMessage = pcall(function()
        text = TextService:FilterStringAsync(summary, summarizer)
    end)
    if success then
        return text
    elseif errorMessage then
        print("Error filtering message:", errorMessage)
    end
end 

game.ReplicatedStorage.FilterEvent.OnServerEvent:Connect(Filter)

function sendFiltered()
    wait (0.1)
    local TextService = game:GetService("TextService")
    local sumname = game.ServerStorage.Summarizer.Value
    local filteredMessage = ""
    success, errorMessage = pcall(function()
        filteredMessage = text:GetNonChatStringForBroadcastAsync()
    end)
    if success then
        return filteredMessage
    elseif errorMessage then
        print("Error filtering message:", errorMessage)
    end
    return false
end

game.ReplicatedStorage.Filter.OnServerInvoke = sendFiltered()

Thanks in advance for the help!