Temu Did Not Refund My Order Despite Claiming the Transaction Was Completed

Temu did not issue a refund. I canceled my order immediately, and Temu sent me a document claiming the refund had been processed, but it never appeared on my card. When I contacted my bank, they confirmed that no refund had been made by Temu. I have already provided all the necessary transaction details to Temu, yet no progress has been made. Despite my repeated efforts to follow up on the matter, customer support has been unresponsive and unhelpful. Temu is now asking for a written document from the bank, but the bank stated that they do not provide such documents. How will Temu resolve this issue? This has been a complete disappointment. If the problem is not resolved, I will file a complaint with the relevant authorities.