Letter to the manager of driving institute

Please correct this letter

Dear Sir,

This is to invite your attention to an important matter

I have been assigned driving classes on 19th and 20th of this month. As these dates are declared public holidays I may not have class on these days. I shall be grateful if you could inform me the date and time of new classes.

Expecting an early reply from you

Yours faithfully,
Muktha Naïve.

Dear Sir,

This is to invite your attention to an important matter

I have been assigned driving classes on 19th and 20th of this month. As these dates are declared public holidays I may not have class on these days. I shall be grateful if you could inform me the fresh date and time for holding the above classes.

Expecting an early reply from you

Yours faithfully,
Muktha Naïve.