Vendor Not Returning The Advance

For my business I took a quotation from a vendor. Based on that I had given advance. During delivery, I changed/had not taken few items, hence the invoice value reduced than quoted value. Since I had already paid advance based on quotation, I end up paying 1.25 lacs more than the actual materials received. For a month, I have not demanded the transfer of balance with assumption to adjust the amount with further purchase. But, after one and a half month I decided to shut down my business, hence asked the vendor to return the excess amount due. After multiple meeting, calls, emails the vendor is not responding. What to do please suggest.