WDS Stopped Working

Last summer I set up WDS on a HyperV VM to deploy images on school computers. Worked great. I haven’t had to use the WDS server for a while. Now I want to create a new image and deploy them to all the student lab computers and school laptops. However, WDS does not seem to work now.

I get the error PXE-E16: No valid offer received.

googling the error, I don’t see a solution that is relevant for what I am doing.

Any suggestions on what to look for?