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Respected Sir,
Dear [Customer Name]
Sub: Apology for inconvenience
Please accept our sincere apology. We are very sorry to have charged you twice for the same product.
I am the Manager of XXX Hotel and I am writing this letter to you in order to express our sincere apologies for all the inconveniences that you were exposed to from our side.
It was clearly a mistake at our end and not one that we take lightly. We can certainly appreciate your shock when seeing double the amount expected on your credit card statement.
I am once again sorry and I express the same on the behalf of our hotel management since we do not want to lose a regular customer like you due to silly reasons.
Dear {Receiver}
On behalf of {Hotel Name}, please accept my apology for your unpleasant stay at the {Hotel branch} on {date}.
We strive to ensure our patrons experience the best visits possible during their travels and we fell short of our goal this time. To prove to you that we take every complaint seriously, we have enclosed an invitation in this letter offering a free two-night stay at any one of our {#} locations.
We hope you will see the improvement and enjoy your time with us in your next visit. Please feel free to contact me if you have any further questions or comments concerning your stay. Thank you.
I understand from my staff that the error was due to a computer glitch in our automated billing system. As a result of this issue, and in order to prevent this from happening in the future, new procedures are being put in place.
In the meantime, we have credited your account for the appropriate amount (include specific dollar value and add a percentage to cover possible interest charges and inconvenience if the dollar amount was large). We hope that this will be sufficient to correct the error and address any inconvenience this may have caused you.
We thank you for bringing this to our attention. It will help us improve our operations and services. We very much appreciate your business and hope that you will remain a valued customer.
If there are any other issues that need to be addressed, please don't hesitate to contact me.
Sincerely,
...........
The Manager,