Why is this spitting out "attempt to index nil with 'Text'"?

I'm trying to make a script so you can change your keybinds, and for the most part it's been pretty smooth, however it keeps spitting out "attempt to index nil with 'Text'" in this section of code. All that section of the local script is supposed to do is change the text of the keybindButton, which is a TextButton, and that's in it's own dictionary as well to make things more organized. The keys for the keybindButtons are the exact same as the keys inside KeybindModule.defaultKeybinds. I don't really understand what's wrong here, and everything I've been doing leads to the same error. I only just learned how to manipulate dictionaries a few days ago, so maybe that's my problem lol

Module code:

-- These default keybinds are actually the values I have set --
KeybindModule.defaultKeybinds = {
    toggleInventory = "tab",  
    invDropAll = "rightClick", 
    invDropAmount = "leftClick", 

    interact = "e", 
    ping = "middleClick", 
    weapon1 = "one", 
    weapon2 = "two", 
    weapon3 = "three", 
    switchToGrenade = "g", 
    switchToOrdinance = "q", 
    melee = "f",

    crouch = "c", 
    prone = "leftControl", 
    sprint = "leftShift", 

    shoot = "leftClick", 
    aim = "rightClick", 
    reload = "r", 
    changeFireMode = "v", 
    weaponSpecial = "t"
}

function KeybindModule.getAllKeybinds(player)
    local playerSettings = PlayerData:WaitForChild(player.UserId):WaitForChild("_settings")
    local returningDictionary = {}
    for i, v in pairs(playerSettings:WaitForChild("keybinds"):GetChildren()) do
        returningDictionary[v.Name] = v.Value
    end
    return returningDictionary
end

Local script code:

local keybinds = ControlModule.getAllKeybinds(player)

for keybindKey, keybindValue in pairs(keybinds) do
    if keybindValue == nil or keybindKey == nil then
        keybindButtons[keybindKey].Text = string.upper(ControlModule.defaultKeybinds[keybindKey])
    else
        keybindButtons[keybindKey].Text = string.upper(keybindValue)
    end
end

Any help is greatly appreciated.