Just in case, Official PlayStation Support explains what you need to do to fix:
"If you have had game download problems on your PS5 with download queue and details messages, update your system software to the latest version, boot PS5 in safe mode, then rebuild the database. "
For details on safe mode, Sony refers to the official support page. However, here are the steps required to access the database update and rebuild options:
How do I start my PlayStation system in Safe Mode?
Turn off the console by pressing the power button. The power indicator blinks for a few moments before turning off completely. Once the system is turned off, press and hold the power button again. Release the button after you hear two "beeps": one the first time you press the button and one seven seconds apart. Connect the controller with the USB cable and press the PS button on the controller.
At this point the options that interest you are two in particular, 03, ie "Update system software", and 05, ie "Rebuild database".
In case the solution proposed by Sony does not work, and the download queue bug persists, here you will also find the option to restore PS5 to factory settings. Attention, because then you will have to reinstall or re-download all the games.
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