Need better formats for writing these business letters

I like to verify formats , written English and tone in which the letters have been written . I do not like to sound too polite neither too rude .

Letter1
Date
To
The Manager
....... Bank
....... Branch

Sub: Requesting closure of DMat a/c numbered ....... with DP ID ,,,,,,

Dear Sir/ Madam
I hold a DMat a/c numbered ..... with DP ID ...with your esteemed branch. I have shares whose ISIN have been suspended, there . I would like to close this a/c .
Please take note and take needful actions .
Yours Sincerely
Sudeepa

Letter 2 < Asking for information from the Company about suspended ISIN >
Date
To
The Director
..............Company
................Address

Sub : Requesting for information about company's planning to restore their ISIN number.

Dear Sir/ Madam
I have shares of your company in my D. Mat a/ which I plan to close . Since your company has been barred ISIN listing I cannot make my a/c balance nill . I need to know about your future plans to proceed.
So please forward me the necessary details the earliest.

Yours Sincerely
Sudeepa