Respected Sir/ Madam,
My name is _______ (name) and I am working as _______ (designation) in your reputed company for the last ______ (mention duration).
I am writing this email with immense pleasure and respect. I would like to inform you that I have been working hard and sincerely to present my dedication for the growth of the company. I have worked overtime as and when required by the company. I believe that I deserve some bonus for the same. You can check my record with my seniors and coworkers.
It is to request you to kindly consider my request and doing the needful. I shall be highly obliged.
____________ (Contact details)