B2B WRONGLY UPLOADED HOW TO RECTIFY

DEar Sir,

We have uploaded b2b of July 19 for a customer . The customer has not checked the details.  Now they found that the july month invoices has not be uploaded and they deducted the gst payment. AFter we checked it has been found that gstin has been wrongly entered for that customer. Now what should we do. How to correct and make the customer availabiity of gst credit and how to submit in gst . Pleas update ?