CAC not showing valid client certificates

Question

Encountering the following error when trying to use a CaC:

No valid client certificate found in the request. No valid certificates found in the user's certificate store. Please try again after closing and reopening the browser and choose a different authentication method.

Error details: The request did not contain a valid client certificate that can be used for authentication. This occurs when there are no valid certificates on the client computer, for example if all certificates have expired or been revoked.

I reviewed the certificates listed in my Edge browser settings, and I cleared old certificates leaving only the recent/currently active certs. Doing this seemed to do the trick and I was able to access CaC sites. However, this no longer works and I'm encountering the same error. Restarting sometimes clears up the issue, but that is no longer effective either.