Trendyol Order Issue with Power Tools Seller - Missing Product Components

I purchased an item from the Power Tools seller on the Trendyol app. Unfortunately, the item I received was not complete. I contacted Trendyol for help, but the seller insisted that the product was shipped in its entirety. After reaching out to Trendyol's shipping service, they confirmed that only a portion of my order was delivered.
Both Trendyol and the seller are refusing to take responsibility for the missing components. I received my product with missing parts, and I have lost confidence in the sellers. I am uncertain about the next course of action, but I will inform the appropriate authorities and contemplate pursuing legal measures.