I'd like to try this one...
We received a complaint(complaints?) from our customer yesterday (that?):
1) The Lot number was incorrect, which caused confusion about the serial number during the inspection on June 18 for 11640 pcs GH236.
This is a mistake due to carelessness and it has happened several times.
2) Our customer arrived at your factory on June 12 and 16. However, he did not find the production line for GH236. Please provide us with your production data to submit to our customer, which will prove that products were produced in your factory.
We look forward to your prompt improvement and your information ASAP.
Please do not trust my corrections. I'm not confident enough....
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