Problems with formatting

I just got my WD Portable 2TB model no. 25061. It came as an ExFat drive and I wanted to use NTFS. When I tried to format it through Windows, there was an error window saying the formatting failed. I ejected and tried on another computer and suddenly the HDD was recognized as a ExFat with a capacity for only 500GB. I did try to convert the MBR to GPT but it just cannot be done - the option simply can’t be selected. I even downloaded the Data Lifeguard Diagnostics for Windows and it shows an error window at the beggining of the scan.

Does anyone know what could that be and if there is something to do? Or is it a physical issue?

Welcome to the Community.

Which operating system do you use? What happens if you delete the entire partition within Windows Disk Management in order to attempt formatting the drive while it has a RAW partition?