NOT A TEACHER!
It is very important to notice that different countries may have different formats for formal letters. For example, in the United States of America, in the subject line we would write:
"RE: Request for Personal Loan
In reference to the above subject, our staff members, Mr.X and Mr. Y, have requested a personal loan in the amount of $000.00, each, for their vacation expenditure.
They are willing to repay it within six months from their monthly salary.
I would request you to look into this matter and kindly approve the loan as requested."