WD External 500 GB spin sound my datas are not accessible

I got a replacement for my external 500 GB hard disk, within 4 months the new one is giving spin sound and it shows 2TB

Please help I am having valid datas on that

Let me see if I understand the problem. Your external drive was 500GB and after 4 months It now registers to 2TB?

Is it possible that you post a screen shot of the problem and also state the Operating System you are running. Thanks.