Attachments are suddenly winmail.dat; how can one change it?

Using Apple Mail Version 16.0 (3826.600.51.1.1) in Sequoia 15.5

Suddenly my attachments are being sent as winmail.dat. This has never happened before. My email goes through Microsoft Exchange at Godaddy. I haven't contacted them yet; I'm hoping someone here can tell me how to change it back. I'd prefer not to have to use some sort of translation app.