The request could not be performed because of an i/o device error

When I connect my WD external drive to my computer facing following problem
“the request could not be performed because of an i/o device error”

Please let me know how I can retrieve my data and fixed it

This particular error message points out to a databridge (Controller) problem. If replacing the USB cable does not allow for your unit to be recognized and stored data has no backup then I’d recommend contacting a professional data recovery service company.