I have possession of property. But not in my name. What should i do?

You have two possible course of actions:

i. Suit for specific performance seeking execution of sale deed: As you have stated, there is an oral agreement between you and the registered owner and in the furtherance of the same, both the parties have performed their obligations except for the execution of a sale deed.

Although the Indian law stipulates that the agreement to sell immovable property must be in writing and registered, however, Hon'ble Supreme Court in Brij Mohan and others Versus Sugra Begum and other, (1990) 4 Supreme Court Cases 147 had held the following:

"We agree with the contention of the learned counsel for the appellants to the extent that there is no requirement of law that an agreement or contract of sale of immovable property should only be in writing. However, in a case where the plaintiffs come forward to seek a decree for specific performance of contract of sale of immovable property on the basis of an oral agreement alone, heavy burden lies on the plaintiffs to prove that there was consensus ad idem between the parties for a concluded oral agreement for sale of immovable property. Whether there was such a concluded oral contract or not would be a question of act to be determined in the facts and circumstances of each individual case. It has to be established by the plaintiffs that vital and fundamental terms for sale of immovable property were concluded between the parties orally and a written agreement if any to be executed subsequently would only be a formal agreement incorporating such terms which had already been settled and concluded in the oral agreement"

So therefore the burden of proof lies upon you to show that the said contract has already been completed and the execution of the sale deed is a mere formality. 

ii. Second option is going for a suit for declaration of title by adverse possession: Adverse possession is a method of acquiring title to a property by possession for a statutory period under certain conditions. Under Indian laws, the statutory period is of 12 years and in your case, you have stayed beyond the statutory period, hence you can file a suit for declaration of title by adverse possession and prove that the necessary ingredients required under the statute have been fulfilled. 

A person who claims adverse possession should show: 

(a) on what date he came into possession,
(b) what was the nature of his possession, 
(c) whether the factum of possession was known to the other party, 
(d) how long his possession has continued, and 
(e) his possession was open and undisturbed. 

Once the above facts are established, the Court shall pass a decree for declaration of title by adverse possession.