Attention Required Notification Blocked Printing- How to Fix it?

First time on my HP Envy 4520 printer, I have seen an attention-required notification. This notification blocked the printing process on my printer. I have tried restarting my printer several times, but it did not help me. Please provide some guide to fix it.
Response By- [Kelvin Morton]
Hello there. The attention required notification occurs due to outdated firmware drivers or some other technical problems. It may also occur due to outdated Windows, or improper functioning of spooler services. Please read our detailed article on- how to fix HP printer attention required message.