LOST BAG BUT AIRLINE NOT TAKING RESPONSIBILITY OR GIVING CLAIM

My name is Rajeev and I am staying in Namibia. I had a very very bad experience with Airlink. I flew from Walvisbay, Namibia to Johannesburg, South Afirca on 28th of October 2021. I have lost my bag on arrival and Air link doesnt want to give me any claim or taking any responsibility for my lost bag. According to them some passenger took my bag and gone but they dont want to help me to trace the person or wanted to give me the claim. They are just passing the responsibility and ask me to file a police case before they give me any claim, on their request i have complained to police, still they dont want to give me any claim. Saying its not their fault. This is the kind of service they give to people. Really pathetic. It is their resposibility to find the person if the person wrongly took and gone, its their passenger at the end of the day. This kind of service is Un acceptable . How the people can fly with them if they are so irresponsible for the passengers baggage.