R K Jewells - During the service

Dear Sir/Madam,
I purchased a Mangalsutra from R K Jewellers in ****. A few days ago, I noticed a defect in it, so I handed it over for repair on April **. At the showroom, they weighed the item and issued me a receipt. I was not looking at the weighing machine while the item was being weighed.
I received the item back on April **; my brother collected it by presenting the receipt. Upon inspecting it, I discovered that the lock (clasp) was missing from the Mangalsutra. I immediately called the showroom. They claimed that the item had never had a lock to begin with. I requested that they show me the CCTV footage to resolve my doubts. They asked me to call back the following day (April **). I called them as instructed, reiterated my issue, and requested to view the CCTV footage. They replied, "You may come in an hour." I responded, "It is not possible for me to come within an hour; could I come in the evening instead?" They refused to grant permission for an evening visit and told me that I could come the next day.
I visited the showroom on May *, as instructed. Initially, they were unwilling to show the footage. After some time, they stated that they would speak with their owner. Subsequently, they confirmed that the owner would arrive within two hours and would show me the footage. A while later, the showroom owner arrived and stated that they did not possess any footage from April **, and therefore, they could not do anything to assist me.

According to state government regulations, it is mandatory to retain CCTV footage for a period of ** days; yet, we are merely requesting footage from five days ago, and they are refusing to provide it.