Paste problems

Hello. My name is Kohei from Japan. I have been using your app for 2 years.
But suddenly the app is no longer available. To be more precise, I can copy, and the copied items are stocked properly, but I can no longer paste them well. I can drag and drop to paste on this app, but I can no longer double click to paste.
If you know how to fix this problem, please let me know.