Unpaid rent (10+ yrs.), tenant missing, How to get possession?

-My shop was built in June 1989. I let out the same in December 1989 with rent agreement which clearly mentions that Act no.13, 1972 does not apply. -The tenant had not paid the rent since [deleted] and the shop is closed since then. -He was living in a rented accommodation in our town as mentioned in the agreement. I inquired about his whereabouts at the location mentioned in the agreement, but I found that he have left the town. His location is now unknown to me as well as the nearby residents & shop owners of that locality. This means he left the town without handing over the shop. -I have discussed the same with a practicing lawyer. He said that you have to issue a claim notice to tenant & if he does not receive the notice then we can't claim your property in the court. -Now as the whereabouts of the tenant is unknown to me as well as the nearby residents & shop owners, How can I claim my property back? What sections & rulings would be applicable? -Also, if this tenant's location continues to remain unknown, then will my property remain in his possession, given that the shop remains closed since January 2005 & without rent payment? Kindly advice. Sincere thanks Deepak Kumar Tehsil- Nagina Dist.- Bijnor UP