when im using samsung fast wireless charger there is decrease in battery percentage sometime and when iam watching movie at that time im charging wirelessly there is no increase in battery percentage, it will remains constant or it will be decreases ... #say_some_solution
You should know that Wireless charging by Samsung is one of the fastest, still, its wireless and its very slow. its that slow that You phone's consumption surpasses the charging speed. It's not recommended by samsung, but if you want to use your phone while charging, use wired charging. It will work just fine. Wireless Charging is not meant so that phone can be used while charging anyways.
"Thank you for Joining Samsung community. We would recommend taking some troubleshooting steps to further isolate what you may be experiencing. Find troubleshooting steps on provided link http://www.samsung.com/in/support/skp/faq/1101689. Please let the community know what steps you have taken and if you have noticed any changes or improvements. This will help the Community to provide you steps without repeating any steps you may have already taken. "