Myntra - Product is missing

I have placed an order of Tommy Hilfiger Silver-toned Aria Analog watch on **th June along with ** other items. It is supposed to deliver in a package containing * items. But when we opened it there was only * products in the package. The package was tapped from the top. Looks like it was torn and then taped back together.

As soon as I found out that the watch is missing, I registered a complaint and called customer care. They assured me that my concern will be addressed asap.

After several emails and calls, they updated me that the refund request is being denied and they closed my complaint. Then I called them again and told them the condition of the received package and shared pictures with them. Then again they closed my request and denied a refund saying as per the package was completely sealed. So I shared CCTV footage of the unboxing of the package and tried to prove to them that I am not lying.
I am boiled up to the core as my expensive watch is missing.
I have been shopping mantra for a very long time and have been their loyal customer. I have never filed unnecessary complaints. I consider myself their regular customer and don't expect this kind of service and treatment.
Clearly, the mistake has happened somewhere in logistics. I they dont want to do their job, because we shop from such an established e-commerce platform hoping not to be looted.
I have also talked to my local office and they said no inquiry has been done in their office. Clearly, myntra is just lying to me. If they are saying that the package is being delivered with the item and sealed, then I want proof of that. I have given them unboxing video as proof that it is not being delivered and now I want proof from them that it is being delivered.
We shop from such platform. Is that our fault? Is being myntra loyal customer for years my fault?
The product being shipped doesn't qualify that the product will get delivered too.
This is very sad to know how online customers are being treated.
The reasons they have given for not refunding me is all a lie. I have attached their response screenshot.
They are saying as per packaging footage the correct product was shipped. - If it is being shipped then why it was not delivered?
They are saying that the product was sealed in tamper-proof packaging- I have already shared the picture as well as a video of the torn package when received
They are saying no instance of package tampering was reported- I have reported package tempering and given all the proof as well.

All their justifications are just a lie. They are just scamming the customers and looting them.
I want justice. I want my money back.