1TB WD Green internal I/O Error

My 1TB WD Green returns a lot of internal I/o errors while writing data to disk (and sometimes while reading but most of the times it’s while writing). it happens most of the time but not all the times.
I changed SATA cable and SATA ports but no change.
S.M.A.R.T on crystaldiskinfo does not report any problems.
WD lifegaurd tool would succeed with fast scan (and sometimes it freezes due to that internal IO error). BUT it always freezes with extended scans.
whenever it starts behaving like that, it would be unmounted by Windows and would remain inaccessible until I completely disconnect it from power for 5 to 10 minutes so that I can access its contents again.
It does NOT make any clicking noises

Internal I/O error indicates that the content, volume or physical hard disk may be damaged, corrupted and in need of repair. You may run Complete Drive Test using Windows Data Lifeguard Diagnostic and check test results.
If it fails or come with any error message, means drive is no longer accessible and need to go for another.

I would recomend you to transfer the data as soon as possible to another drive if you dont have any backup…