Ecom Express — why you need a scan of our private id cards??

Ecom express doesnt deliver the product until we give them a scan of our aadhar card. This is illegal. No one can create a database of such scans. I am ready to show it as a prrof of address and identity, but why you need to take a scan of it? You can personally verify it and deliver the courier after that.
The delivery boys behave unprofessionally if we deny the scan (Even if we are ready to show them the id proof for verification)