Dear Sir/Madam,

I am writing this letter to sincerely apologize for my recent mistake. I realize that my actions have caused inconvenience and may have affected the team's progress. I deeply regret any trouble I have caused.

The task I was responsible for was not completed on time, which delayed the project. This was due to my poor time management skills and lack of attention to detail. I understand that these are important qualities that are necessary for the success of our team.

In the future, I will make sure to prioritize my tasks and ensure that deadlines are met. I will also pay more attention to details and double-check my work before submission. I am committed to improving myself and contributing positively to our team.

Once again, I apologize for any inconvenience caused and appreciate your understanding.

Sincerely,

[Your Name]