I Face Missing Pillowcase Issue After Buying King Size Duvet Set From Marks & Spencer Online

I purchased a King size duvet cover set from the Marks & Spencer online store. However, when the product arrived, there was only one pillowcase inside the package. I contacted customer service and had two separate conversations. In both cases, they informed me that the item was out of stock and that they couldn’t assist further. Yet, according to the online system, the same pattern is available in the double size version—especially at the Metropol branch. Even though I ordered the King size version, I got the impression that they simply didn’t want to split the double set in stock.

For a solution, I was only offered either a refund or a 15% discount coupon. I don’t want to return the product because I genuinely like it; I just expect them to send me the missing pillowcase.

My order number is 3040889774814361. I purchased the item for ₺2,299.99 using my credit card, and I am still within the return/exchange period. From a brand like Marks & Spencer, I expected more effort to resolve this issue.