Documents for transportation of goods from unregistered person - Goods and Services Tax - GST

Hi, can anyone help me with the required documents to be carried while transporting the goods. 1.In the month of March 2025 I sold goods to unregistered person in Tamil Nadu and I am from Karnataka. Now the unregistered person is not able to sell the goods and he wants to return goods back to me. how can I transport the goods from unregistered person back to Karnataka. What are the documents required, and who is required to generate e way bill, and the unregistered person is not ready to issue any documents ( because he is not registered) value of supply 2,61,000. ( what are the documents need to be carried while transporting the goods back, it is the case of sales return from unregistered person)