Script Timeout: exhausted allowed execution time (ROBLOX)

I am making a game for ROBLOX, and I have ran into a problem.

I am making a script so that when the player runs, the FOV of the camera will shoot up, acting like your really fast.

I have successfully made the code, however when ran in studio or the client, it freezes the game and puts a "Script Timeout: exhausted allowed execution time" in the output.

Is there any way to fix this?

Code here:

local UserInputService = game:GetService("UserInputService")
local TweenService = game:GetService("TweenService")
local player = game.Players.LocalPlayer
local Humanoid = script.Parent:WaitForChild("Humanoid")
local Camera = workspace.CurrentCamera
local FovRun = TweenService:Create(workspace.CurrentCamera, TweenInfo.new(0.5), {FieldOfView = 75})
local FovWalk = TweenService:Create(workspace.CurrentCamera, TweenInfo.new(0.5), {FieldOfView = 70})
local Running = false

UserInputService.InputBegan:Connect(function(Key, IsTyping)
    if Key.KeyCode == Enum.KeyCode.LeftShift and not IsTyping then
        if (Humanoid.MoveDirection:Dot(Humanoid.Parent:WaitForChild("HumanoidRootPart").CFrame.LookVector) > 0) then
            if Running then
                FovWalk:Play()
                Running = false
                Humanoid.WalkSpeed = Humanoid.WalkSpeed - 8
            end
            Running = true
            Humanoid.WalkSpeed = Humanoid.WalkSpeed + 8
            FovRun:Play()
            elseif Humanoid.Health > Humanoid.MaxHealth / 1.5 then
                repeat
                until not Running
            if Humanoid.Health < Humanoid.MaxHealth / 1.5 then
                repeat
                until not Running
            end
        else
            if Running then
                FovWalk:Play()
                Running = false
                Humanoid.WalkSpeed = Humanoid.WalkSpeed - 8
            end
        end
    end
end)

repeat
until not Running

This is an infinite loop. If you enter it and Running is true your code will run it forever as Running is not being updated in the loop's body.

Roblox will realize that your code is stuck and throw that error message.