It seems like the problem was that the helicopter was invisible due to a mod that modifies its windows... If you have any mod which does something to the helicopter it will be invisible/glitched. This does not applies to skins tho, it will work perfectly if you only have skins (it worked with a Hatsune Miku one lol)

OLD: (the problem that I was facing)

I dont know why this happens but when the fireworks start (after the 10 minutes surviving on playground) the helicopter dont come to the rescue... This happens to me everytime I try to finish the map, wasting my time :/
Here is the proof,,, it just stay there glitched... I saw another person in the comments having the same issue, thats why I write this.
https://ibb.co/5BBGyhH
https://www.youtube.com/watch?v=O3RWIVTofa8&feature=youtu.be (skip to 10:15 to ignore my ♥♥♥♥♥♥ gaming and to see when the fireworks start)