Myntra.com — I am complaining about the refund.

I received my product on 14th July 2021 but I initiated the return request. Delivery executive from xpressbees came and picked up my product on 15th July at around 1:00 pm in the noon and he didn't provide me any receipt.
In the evening I received a message that the pickup of the product has failed.
I talked with the delivery executive and he confirmed that this is a technical error and no need to worry it will be fine in some time.
Till now I am talking with Myntra customer support on a regular basis.
No solution has found till yet. They said we didn't receive the product on our desk. We are unable to refund the amount. The status of the product is delivered despite that It has been already picked up by xpressbees person.