A buyer has requested to cancel the order when the order was completed and on the basis of I can't fix the error but he was not replying

[techychunky]

Guys, A buyer has requested to cancel the order. How this can fair? And when the order was completed.

And also he requested to cancel the order on the basis of the error can’t be fixed by me. But the buyer is not responding that’s why the error can’t be solved. Please anybody tell me what to do. This is my first order

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