N11 Sold Me a Product with Missing Parts and Refused to Resolve the Issue

The product I purchased from the N11 site arrived with missing box contents, rendering it unusable. I contacted MSI Global, and they directed me to ServisPoint, their authorized service center in Turkey. I must commend the ServisPoint team for being attentive and solution-oriented. After mutual discussions, the service decided on a return or exchange. I relayed this decision to the seller, who then demanded a printed service form on A4 paper sent by cargo, seemingly to complicate the process and cause financial loss. Despite the cargo being delivered 16 days ago, the seller has taken no action. N11 claims they cannot reach the seller but still allows them to operate on their platform, leaving customers stranded. Although I am entitled to a replacement, they now say a refund will be issued, which still has not happened. If I choose to reorder the same product, I would have to pay a much higher price, not to mention the time and money I have already spent on shipping. Thanks to this "wonderful" shopping experience, I have officially submitted a complaint to the Consumer Arbitration Committee. I will never purchase anything from N11 again.