From LINE version 6.8.2, we have added a feature to automatically exchange LINE Points for LINE Coins when purchasing stickers or themes. For this reason, you are no longer able to manually exchange Points for Coins by going to Use from the LINE Points menu.
The amount of Coins you see on the item purchase screen is determined as follows:
Your Coin balance = the Coins you purchased + the amount of Coins that can be exchanged from your current Point balance.
If you are able to purchase an item using the Coins you charged, Points will not be exchanged.