SMART error - HELP

I have purchased a WD my Passport 500GB USB 3.0 (WDBACY5000ABK) from an Online Retailer - Ebay.in.

I had my WD delivered before 3-4 days. I installed the WD Smartware software included with the Drive and did a Quick Format using WD Quick Formatter (also included).

After that i tested my drive using Diagnostics from WD Smartware.

Quick SMART Status :: PASSED
Quick Drive Test :: FAILED
Complete Drive Test :: Did not run the test.

So, i went through the WD FAQ and downloaded Windows Data Lifeguard Diagnostics and tested my WD

Quck Test :: Failed with error code 07 (which means drive is damaged and needs replacement - went through error codes)

So, as per directions i registered my WD for replacement - RMA.

After generation of RMA, i came across WRITE ZEROS under Windows Data Lifeguard Diagnostics.
I did a FULL ERASE using WRITE ZEROS (took about 4 and a half hours), did a WD Smart Format, checked for all the tests. Its all working fine now.

WD SMARTWARE TESTS ::

Quick SMART Status :: PASSED
Quick Drive Test :: PASSED
Complete Drive Test :: PASSED

Windows Data Lifeguard Diagnostics´╗┐ TESTS ::

Quick Test : PASSED

So, what am i suppose to do, as i have already generated an RMA for replacement bcoz of SMART error (error code : 07 / 0007).
Should i still go ahead and replace my WD?
Also, what if after cancelling RMA, i get some error or fault in the later phase and i need to replace the drive. Will i be able to do that?

You can cancel the RMA, you should be able to replace it latter on, if you determent that the drive is faulty and need to be replaced.

Thank you for the reply.

But i feel i will have to replace my WD as i heard some clicking sounds while i was using it.

Sorry but can anyone please let me know how can i Cancel my current RMA and Regenarate a new one.

As my problem has changed from SMART error to something else.

OR Can i just attach a new letter along with the courier package decribing the change in Fault.

What RMA you did? Advance or standard?