Thanks for reaching out. We are sorry for the trouble with Photoshop's neural filters. We are here to help!
Could you please share the system info from Photoshop > Help > System Info, copy & paste the information here? Does this happen with any specific image or document, or do all documents behave similarly? Does the Neural filter workspace show any error code or messages? Are you working on a personal computer, or is it a shared computer? Have you tried any troubleshooting steps?
Close Photoshop & sign out of the Creative Cloud desktop app.
Restart the computer and sign in to the Creative Cloud app & Photoshop to check if the filters are available.