Wireless printer problem

Provided it has been working, try powering down the printer and powering it back up again. While you do that, do the same with your wireless router. Let them restart, then try printing again.

Whatever you do, do not delete that printer from Printers & Scanners. macOS will respect existing printer drivers and will not delete them, but will not permit installation of them again.

Excerpted from About AirPrint - Apple Support:

"Learn how to print from your Mac or print from your iOS device, and learn what to do if you can't print."

Recent macOS versions support only AirPrint-enabled printers and multifunction devices, and I can't find the Samsung CLP-325W printer in that list. Are you certain it's AirPrint-enabled? Were you able print to it in the past, prior to upgrading macOS?

You're welcome. Glad to help.

Whatever you do, do not delete that printer from Printers & Scanners. macOS will respect existing printer drivers and will not delete them, but will not permit installation of them again.

Related to that advice: if you want to keep that printer in service, do not perform a so-called "clean install" of macOS, which would eliminate those old drivers. If you were to do that, it would not be possible to install them again.

Although there is no guarantee it will remain their practice, to date Apple's macOS upgrades have not removed existing drivers. That's the reason old, pre-AirPrint printers continue to work.