Hyundai Motor India — I am complaining about engine oil leak immediate after service

Hi, I had got my creta sx 2018 model car routine service from Kusalava motor pvt limited, Vijayawada, Andhra Pradesh, recently on 5th August 2021.
Yesterday night (20/08/2021), had engine oil leak indicating malfunction.
In an emergency situation repair got done by local mechanic.
It was found that engine bolt was lost and leading to loss of engine oil, due to malfitting of bolt and not checking properly before car delivery to customer.

It was major and grave mistake on servicing part, it would have led to seizing of engine and spoiling of engine and also causing major accident leading passengers and driver death..