is it permissible to buy or purchase a common space in an Apartment. by any third party?

Question

because in our apartment that a common space between my flat and other flat meant for our two flat owners convenience, is now in dispute because one flat owner of our apartyment has claiming that I have purchased the said space from the Builder. It is permissible under law.

Answer 1

As long as the common space is not a access area, and can be demarked it is possible to purchase it.

Answer 2

yes