Q: I am trying to update my firmware for my Thunder bolt display. It says the software is not available. My display has quit working.

Hello cbj31968,

Thank you for using Apple Support Communities. 

I understand that you are trying to update the firmware for your Thunderbolt Display. Let's first make sure that you are following the correct process for that. I see you posted from this article: About Thunderbolt Display Firmware Update 1.2 

Were you able to complete all the steps on the article?

If you are still having issues with the display not working, this article should be of help: Get help with video issues on external displays connected to your Mac

Best regards.