STEP 1: Visit the Product Listing page 

STEP 2: Click Bulk edit button from the drop-down menu in More Action

STEP 3: Clicking the Bulk Edit button, you need to select the Form & To date of product creation. Then, click the Export button to export the product CSV file.

STEP 4: Save window will Popup & User needs to save the file

STEP 5: Go to the saved file and make the changes in the Product Quantity/Price wherever required. Do not forget to save the file after completing the changes.

STEP 6: Now upload file you changed

STEP 7: First press Validate button then Submit

PLEASE NOTE: File update takes time at least 30 minutes.