writing agreement letter

'hi , i am an HR Intern and would like assistance in writing a letter to an employee here at work. her contract is ending in November and will be renewed for January. i need to write a letter stating we will carry the leave days over instead of paying terminating them and paying her off for them so she is able to go on leave for December. i wrote somewhat a letter so please correct it.

This letter serves as an agreement to our discussion that your contract expiring end of November will be renewed as from beginning of December. Your accumulated leave days as of end of November are 10.33 days. You agree to have the"Company name carry the leave days over to the new contract instead of terminating them."