A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
This is a known issue due to a recent update. See article https://support.microsoft.com/servicing/office/hotfix/excel/5002914
Are you using Office 2021 LTSC/Standard/Pro Plus editon - I am guessing so based on your current version number.
In this case, please type cmd in the search on the taskbar. Don't press enter key yet. Instead, choose "run as administrator" to launch Command Prompt.
Then run this command - copy the entire command, and make sure the quotation mark at the beginning is included to avoid syntax error. After you run it and restart, it should work.
"C:\Program Files\Common Files\Microsoft Shared\ClickToRun\OfficeC2RClient.exe" /update user updatetoversion=16.0.14334.20848