Well today I visited my local municipality office and ask them to make a letter on a government letter-pad which certify that my DoB is <dd/mm/yyyy> and mentioned that when I was born there was no system of Birth Certificate Registration System.
I hope this will work as per OOPNP explanation:
Provide a copy of your birth certificate or an acceptable national document where an original birth certificate is not available (i.e., letter from appropriate government authority indicating why your birth certificate is not available).
Do you think I can send the original copy or make a xerox and notarized from public notary ?
Thanks.