can nvc change interview location?

That's particularly true if you are on a waiting list for an available visa number. This would happen because you're not an "immediate relative" of a U.S. citizen or in another category where demand for immigrant visas is lower than supply, and your "priority date" isn't yet current. Some people wait years, during which the NVC might be the sole holder of their file.

Given the NVC's important to eventually moving your case along, it's crucial that you advise it of any changes of address or other contact information.

The NVC has no decision-making power, but plays an important administrative role. It acts as a sort of an intermediary, handling applicants' files after initial petition approval by U.S. Citizenship and Immigration Services (USCIS), maintaining these files while waiting for the applicants to have current priority dates and thus available visas, and then arranging for transfer of the file to the appropriate overseas U.S. consulate or embassy.

Depending on the type of visa you hope to qualify for, your file might be held at the NVC for anywhere from several weeks to several years or even decades.

The NVC is an independent agency, not truly a part of either USCIS or the Department of State. Therefore, you can't count on one of these agencies passing along your latest contact information.

If you wish to change your interview location, a new form DS-160 is not required. The Embassy or Consulate at which you actually apply can access your form using the barcode on your DS-160 confirmation page, which you must bring to the visa interview.