Click the Apple Menu > System Settings (or System Preferences). Go to Printers & Scanners. Select your printer and click the Print Queue button.
Outdated drivers: Software conflicts between your OS and the printer. How to Clear the Printer Queue on Windows 10 and 11
You check your computer. The document is sitting there in the queue, status: "Printing." But the printer is idle. You try to cancel it, but nothing happens. You try to print a new document, but the old one is blocking the way.