A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
The Copy & Paste problem is a widely reported bug in Excel caused by the latest Office update (KB5002914).
Try uninstalling that update and restart your PC.
If you are unable to uninstall the update, what version of Office do you use, is that Office 2019, 2021, 2024 or a Microsoft 365 subscription.