OnTriggerEnter not called after importing a package that works fine

So i made my game in unity 5.2.
The game works fines in the editor. My character collects coins just fine. I use OnTriggerEnter to detect the coin. If i build the game for android the apk works. The coin is collected.

I’ve put all my files into one folder. That folder has all the scenes, materials, prefab, models, animators etc. If i export this folder and import it into a new project. The game works fine in the editor again.
The character collects the coin.

But when i build for android and play it on the phone. The character just passes through walls coins with no detection at all. The OnTriggerEnter code is not called. I also noticed that OnCollisionEnter is not called yet the collisions do take place.

I changed the unity version to unity 5.3 but there was no luck

What could i have done wrong when exporting the package.
Or how should i export my package to make the code to be detected on a new project
(I intend to sell the package thats why im exporting it)

That sounds very strange. That it will work as intended in the editor but not on build. I recommend downloading the Unity Remote app for your phone. You’ll be able to play the game on your android device whilst being able to view the console for logs. Also recommend adding a Debug.Log(“I was collected”); into your OnTriggerEnter function.
Finally, i’ve not used much of OnTriggerEnter and have always found OnCollisionEnter working fine for me.

If you’re still struggling, share your code and I’ll be happy to review.