Is it confusing when i purchase “Be Theme” they didn’t give the revolution slider plugin, only the data demo of revolution slider?
You should contact the author of ‘Be Theme’ to get your answer. Only they can provide you the best assistance. Cheers. 
It says that my purchase code already expired. How can I say it to them?
You have to contact with Be Theme author with your purchase code hope they will help you and your problem will solved.
if your purchase code is expire then you can get extended license other wise you are not able to get help from them.
If your purchase code is expire then you are not able to get item support any of item from any of author.