New MacOS (Sequoia) mail's signature does not recognize Windows Outlook.

New MacOS (Sequoia) mail's signature does not recognize Windows Outlook.

The email receiver is receiving an HTML file instead of a signature when I attached something.

The signature without attachment looks okay.

I checked it on a different Mac and on different versions of Windows of Outlook.

The error remains the same. But browser can.

here is the screen shoot.