Inter state transfer

I had made a sale in Kerala for an individual who is not having any company or entity registered in his name. The invoice value is around 1 lakh inrPurpose of this action is for distributing a newly introduced product to his friends and relatives as he has plans in future to start up the company and have a dealership. When from Karnataka we made the sale we have added 14.5 of VAT also I would like to know what all documents are required in this case to transport the said consignment to Kerala.At check post the customer has received a notice from sales tax that tax evasion is suspected and he has been fined some what half of the invoice amount. Please suggest me how to sort out this thing.Note - 1- products are not for sale.2- was there any documents which were to be submitted by the customer?3 - what all were the document which had to be submitted by the consigner?4- as asked by the transporter (Vrl) we had given invoice copy, e sugam, and form 16 at the time of sending the productsPlease revert it will be a help for me to sort out te things