Experiencing Challenges in Exchange or Refund for Tommy Hilfiger Coat due to Production Defects

I got this Tommy Hilfiger winter coat in green from the Boyner store at Marmara Park. I wore it just twice, and the color on the neck area started fading and darkening like crazy. It's practically unusable now. So, I decided to send it back to Boyner for a refund or exchange. What do I get in return? A big rejection. No way am I rocking a faulty product like this. I'm demanding either an exchange or my money back until this mess is sorted out. If not, I'm stuck constantly shipping back this flawed item, whoever is in charge, pls, fix the problem, and get this coat replaced. I dropped a good chunk of change, thinking it's a top-notch brand – now Boyner needs to back that up and either exchange this or give me my money back. The receipt number for this product is st-10589787-W3J4. I'm asking for an exchange on this one. There's no way my usage caused this issue – it's a problem with the fabric, plain and simple. I've attached the receipt as a photo for your reference.