WD MY Book Essential 3TB USB 3.0

I need help. Maybe Ia m writing in the wromg section of the community, if so I appologise in advance.
I have a WD my book essential 3tb usb hard disk for 5 years. Until recently its performance was flawless, for the last 2 weeks whenever I try to transfer files to it, freezes - at the beginning the copying or tranfering speed is great, than it falls to zero and the disk freezes… Tried to make a copy of the existing files on the disk, some get copied easily, meanwhile others are ‘not recognized’… Tried the find errors and repair in windows 10 to see if it will be any better, but the problem persists… Is the disk dying?

Apart from trying it on a different PC and trying a different USB cable …

What were the WD Diagnostics results ?

I tried connecting it to another computer, the problem persits… Whenever it comes to copying certain files / folders I get the error message cannot read from the source file or disk (while that is happening I hear clicking/skipping noise like something is stuck). Tried to run. WD diagnostic tool - the quick scan does not find any errors, ran tools to check if there are bad sectors, problems with partitions - all passed well. Still waiting for the detailed scan by the diagnostic tool…
Could be a head problem? If so, how can I know it? Any possible fix? The disk is less than 50% full.