Password protection is useful while a document is in transit. Later, it may become a nuisance. You might need to merge the PDF with other files, convert it to Word, upload it to a portal, or archive it in a system that cannot process encrypted documents.
If you know the password and have the right to modify the document, unlocking creates a normal PDF copy. Keep the protected original if you still need a secure sharing version.
Use Unlock PDF, enter the password, and download the unlocked copy.