enemy NPC spams walking and idle after there are no unit NPC in the field, how do i fix this?

This was pretty painful to fix though i wont get answers in this website and i still need more activities reading to get post in devforum..

Though ill send the video and script to see what hell is happening https://streamable.com/gifvbq

local npc = script.Parent
local global = require(game.Workspace.Enviroment.GlobalVar)

local baseunit = game.Workspace.Enviroment["Base-unit"]
local baseenemy = game.Workspace.Enviroment["Base-Enemy"]

local part = Instance.new("Part")
local weld = Instance.new("WeldConstraint")

weld.Part0 = npc:WaitForChild("HumanoidRootPart")
weld.Part1 = part; weld.Parent = part

part.Name = 'Hitbox'
part.Anchored = false; part.CanCollide = true
part.Massless = true
part.CanCollide = false
part.Transparency = 0.5
part.Size = Vector3.new(3.2, 5.8, 3.8)
part.CFrame = (npc.HumanoidRootPart.CFrame + Vector3.new(0, 0, -part.Size.Z *0.5))
part.Parent = npc

local animation = {
    idle = npc.Idle,
    run = npc.Run,
    atk = npc.Attack
}


local IdleTrack = npc.Humanoid:LoadAnimation(animation.idle)
local AttackTrack = npc.Humanoid:LoadAnimation(animation.atk)
local RunTrack = npc.Humanoid:LoadAnimation(animation.run)

--RunTrack.Looped = true
--IdleTrack.Looped = true

local animtable = {
    ['idle'] = IdleTrack,
    ['run'] = RunTrack,
    ['atk'] = AttackTrack
}

local animstring = 'run'

local pathfinding_service = game:GetService("PathfindingService")

local timer = nil
local idleTimer = 0
local timeAfterAtk = 1.4

local isOn = false

function HasChild(Name, Model)
    for _, Child in pairs(Model:GetChildren()) do
        if Child.Name == Name then
            return true
        end
    end
    return false
end

function onHit()
    if (timer ~= nil and timer <= 0) and isOn then
        for i, entity in pairs(game.Workspace.Unit:GetChildren()) do
            if game.Workspace.Unit:FindFirstChild(entity.Name) then
                local relativePos
                if HasChild('HumanoidRootPart',entity) then
                    relativePos = npc.Hitbox.CFrame:pointToObjectSpace(entity:WaitForChild("HumanoidRootPart").Position)
                end
                if HasChild('HumanoidRootPart',entity) and math.abs(relativePos.X) <= npc.Hitbox.Size.X * 1 * 0.5 and math.abs(relativePos.Z) <= npc.Hitbox.Size.Z * 1 * 0.5 then
                    entity.Humanoid:TakeDamage(55)
                    print(tostring(entity.Name)..' HIT!')
                else
                    print(tostring(entity.Name)..' Dodged!')
                end
            end
        end
        timer = nil
        isOn = false
        idleTimer = timeAfterAtk
    end
end

local curWalk = npc.Humanoid.WalkSpeed

isOn2 = true

function lerp(a, b, t)
    return a + (b - a) * t
end

while wait() do
    if npc.Humanoid.Health <= 0 then
        task.wait(2)
        for i,v in pairs(npc:GetChildren()) do
            if v:IsA("Part") or v:IsA('MeshPart') then
                npc:FindFirstChild(v.Name).CFrame = CFrame.new(Vector3.new(0,-20,0))
            end
        end 
        break
    end

    if AttackTrack.IsPlaying or IdleTrack.IsPlaying or idleTimer >= 0 then
        npc.Humanoid.WalkSpeed = 0
        print('is my reddummy man idling??')
    elseif idleTimer <= 0 then
        npc.Humanoid.WalkSpeed = curWalk
        print('is my reddummy man walking??')
    end
    if not animtable[animstring].isPlaying then
        for i,v in pairs(animtable) do  
            animtable[i]:Stop()
        end
        animtable[animstring]:Play()
    end

    npc.Humanoid:MoveTo(baseunit.Position + Vector3.new(8,0,0))

    for i, entity in pairs(game.Workspace.Unit:GetChildren()) do
        if idleTimer < 0 and (npc:FindFirstChild('HumanoidRootPart').Velocity.Magnitude) >=0.004 and not isOn then
            animstring = 'run'
        else
            animstring = 'idle'
        end
        if game.Workspace.Unit:WaitForChild(entity.Name) then
            local hitbox = npc:WaitForChild('Hitbox')
            local relativePos
            if HasChild('HumanoidRootPart',entity) then
                relativePos = hitbox.CFrame:pointToObjectSpace(entity:WaitForChild("HumanoidRootPart").Position)
            end
            if idleTimer <= 0 and entity:WaitForChild("Humanoid").Health > 0 and math.abs(relativePos.X) <= hitbox.Size.X * 0.8 * 0.5 and math.abs(relativePos.Z) <= hitbox.Size.Z * 0.8 * 0.5 then
                --print(tostring(entity.Name).." is inside")
                animstring = 'atk'
                if not isOn then
                    timer = 0.8
                end
                isOn = true
            elseif idleTimer > 0 and entity:WaitForChild("Humanoid").Health > 0 and math.abs(relativePos.X) <= hitbox.Size.X * 0.8 * 0.5 and math.abs(relativePos.Z) <= hitbox.Size.Z * 0.8 * 0.5 then
                animstring = 'idle'
            end
        end
    end
    onHit()
    if timer ~= nil and timer >= 0 then
        timer -= 0.015
    end
    if idleTimer >= 0 then
        idleTimer -= 0.015
        --print(idleTimer)
    end
end