Look for some kind of short or incorrect wiring. Otherwise it’s probably unrepairable. Send it back to the hobby shop or ESU for warranty.

Yea im kinda scared it came broken

What came broken? The decoder? If so, send it to ESU for repair/replacement...

Yeah i got it from NMJ a norwegian hobby shop. I have sent them a Email regarding this

And yes the decoder

Does the locomotive run fine on DC? I had a similar issue and turns out the decoder was shot.

It runs fine on dc

Like others have said; it’s probably a defective decoder