Apology Letters for Professional Mistakes

Dear {Recipient},

Please accept my sincere apologies for creating a false impression about {product/service} when we spoke {on the phone/via email} {last week/the other day/etc.}. I understand how the lack of information about {the price/features/etc.} could be misleading, which I assure you was not my intention.

To help you understand our {product/service} better, kindly refer to the {factsheet/link/etc.} I've attached.
Please don't hesitate to reach out to me should you have any further questions.

Warm regards,

{Your Name}

Dear {Recipient},

I'm sorry I failed to {file the records/enter the data/schedule the appointment/etc.} that you requested earlier. I didn't mean to be negligent, but {reason} prevented me from completing the task.

I'm not trying to come up with an excuse, though. Please let me know what I can do to sort this out. I'm willing to {stay back after office hours/reach out to the client/etc.}.

Sincerely,
{Your Name}

Dear {Recipient},

I'm sorry I didn't leave you a tip after dining at {name of restaurant} this past {day of the week}.

Please know that it was a complete oversight on my part and not a reflection of your service at all. The service you provided was beyond my expectations and I had a wonderful experience at {name of restaurant} thanks to you. Unfortunately, I was in such a hurry to leave that I forgot to leave a tip—and I only realized it once I was already {home/back at the office}.

Enclosed is a check for {dollar amount} to make it up to you. I have also written a letter to your manager to let {him/her} know about your excellent work ethic.

Kind regards,
{Your Name}

Dear {Recipient},

I apologize for failing to show up to my scheduled interview on {day of the week}. I know this reflects poorly on me as a job candidate, but I assure you I wouldn't have missed such an important appointment unless there was a very good reason.

Unfortunately, {reason for missing interview}, thus I had no choice but to miss my interview. I hope you'll consider rescheduling me. I'm really interested in the position as {reason for interest}.

Thank you for your kind understanding.

Sincerely,
{Your Name}

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