I tend to come across people asking about doing a wrapping background, a lot of times they're given an answer to achieving this but I personally feel there are...
The text states that we will check if ..
"TileBackground.Y is great than or equal to 0."
but the Event screenshot shows Y = 0 and not Y >= 0. Y is unlikely to reach exactly zero and the wrapping therefore won't work. Ensure that you use "greater than or equal to".