Royal Enfield reborn classic 350 crappy service by RE service Center and noise issues in engine since day 2 after buying.

May 2023 I had bought a new royal enfield classic 350 and at day 2 it was having some noise issues I and after 15 km it got worsened had replaced the oil one time myself as the stock oil was black and the noise had reduced but for second time when I took it to Royal Enfield service Center for scheduled maintenance and oil changing they had mixed both the old oil and the new oil which was definitely not good by the time the noise was still there and then I had took it to service Center yesterday for scheduled maintenance and told them to fix the noise and then today I had picked up my bike and then the noise had increased. Can anybody tell me the issue and how can I fix it ? The video is provided below after they had serviced it and this video was taken today with the increased noise listen to it carefully. It is overheating and having tappet noise and engine clatter is quite a lot.