CRZ ( coastal area ) Not recieved O.C. Building of year 2011

Hi, I have purchased a flat in year 2010 and got possession in 2011. In this Building every one got loan approved by all banks like mine State Bank of India, HDFC, ICICI etc. I personally have done documentation in SBI as we know that no agents for SBI loans, we only have to go to Property Valuation and Inspection report by third party and submitted to bank. Now in March 2014 we got Property Tax Bill from Navi mumbai Mahanagar palika as follow. Current Amount : 80,519/- Previous paid amount : 0 Prev pending amount : 3,42,999/- Total pending bill amount : 4,23,518/- and at top of the bill written Without OC Building. After lots of investigation came to know that builder paid few previous bills and it was suppose to be 14,799 for 6 months of whole building(plot). But bcoz of staying without OC, Navi mumbai mahanagar palika (NMMP)is charging us 80,519 for 6 months and why are we not getting OC ? also went to Ward office and came to know that building is inside coastal zone (CRZ) so we are not getting OC. So yearly we are paying property TAX 1,61,038 to NMMP. I was trying to sell my property from last 3 years, but every buyer ask 1st question title clear hai na, ? means do you have OC ? Means If OC is not there my buyer will not get loan and i wont be able to sell my flat..! Many times heard that government has already declared OC for many unauthorised buildings.. don'nt know when will we get OC and i can sell my flat...?