File protected by a password is opened as a text and there isn't password window

Hi, i have an ods file protected by a password.
It worked very well until 5 days ago… It’s open like a text file and there isn’t password window.

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What happened 5 days ago, OS update? LibreOffice update? Crash?

What does it open in, a text editor? Change your file association. Test by opening LibreOffice then opening file from LibreOffice, if it opens as normal then just your operating system’s file association has been changed, set it back to LO using the methods for your OS.