Perhaps there are several reasons for the non-response. One is that you have asked a question that no one can answer, given the minimal information you've provided. You've said the equivalent of "I have a headache. Is it a brain tumor or a hangover?"

You need to do some basic troubleshooting. Try a known good disk. Try formatting a known good floppy in that same drive. Does it successfully complete the format operation? Are disks that fail in that drive known to work in other drives? Etc. You get the picture. Design, then run, experiments to narrow down the possibilities. Then you'll pretty much figure it out without our guessing in vacuo. If you get stuck interpreting the outcome of your experimentation, post back with specifics, and you're likely to get answers.