Should I purchase a property which has both GPA and Registered with my seller.?

I have done a sale of agreement with a seller. Recently he has registered the property at the register officer. Before registering the property, he has GPA with the original owner of the property. He has not shown the GPA papers at the register office while registering the property.

Whether I should ask the seller to cancel the GPA and then buy the property? Or it is not required to cancel the GPA since the property is registered now?