We should furnish our name, father's name etc., with correct initials, spelling, surname etc., when we give at the time of admission or at the time of submitting examination application through the school. The certificate issuing authorities cannot be blamed for spelling difference as many people do have their names with different spelling in the thought of numerology and practice of their own area. In Pondicherry area people write Mourougan for Murugan. In Kerala Mani is written as Moni. In Bengal area Vasu is written as Basu.
It is common to have some mistakes while entering name/s in certificates and it is our duty to check while receiving. This may be due to the steps of both sides. While furnishing our name in application we should take utmost care as a)with or without space b) when we follow some numerology adjustments.
To correct this we have to approach the concerned authority IN PERSON with relevant documents without delay.
Subsequently we should have all certificates, Government IDs like Aadhaar etc., with similar name and spelling.
It seems to be a difficult one in your case as your school is not existing now, you can approach local government educational authorities for getting correction in your certificate. When you are going there you should take the following with you:
1.The school documents, any, whatever you possess.
2.your present aadhaar card
3.any relevant document/s which has your name with correct spelling and surname.
There are chances to get your certificate corrected.
Alternatively, you can approach local advocate with notary who will prepare an affidavit with notary signature for such correction.