A Complete, detailed unity IAP tutorial ?? For android and Ios

I have been following all the manuals, documentations and online tutorials. However, I am still not able to get the IAP working correctly. Any help will be appreciated.

I shared my IAP script in the following question: click

You can use it for your purpose. It has receipt validation and ability to restore the purchases.

All you need it’s just copy the script from the link above and replace the products (just read the comments for more information).

@Unity Technologies please help!

There is a demo scene in the IAP package (which is auto-imported) if you enable inApp purchases in Unity itself.