Amazon Made Returning My Sleeping Bag Complicated After Lowering Its Price

I purchased a high-quality sleeping bag from a reputable brand at a reasonable price through Amazon’s interface from a third-party seller. However, just one day after my purchase, Amazon reduced the price of the same product by ₺1000 in its own listing. I initiated a return request and took the product to the courier company 4 km away, which handled the original delivery. I provided the return codes given by Amazon, but the courier staff said these codes were merely procedural and not valid for processing. Amazon customer service told me they would send a proper code within 72 hours. Although I am not an Amazon employee, I feel like I am being made to work for them, and my tasks are being disrupted. I request that your company resolves this issue and compensate for the inconvenience caused.