Project delay and land owner issues

Hello sir, Our project is got delayed and also builder is absconding. Another issue is that there was a sharing agreement between land owner and builder with 60/ 40 %share means 60 % share belongs to builder and 40% belongs to land owner. This is agreement is done in 2013 when they started the project after that again they made another one sharing agreement in Jan 2014 which says that land is holding only 9 flats and remaining portion of his share has been sold to builder. On that basis we have booked the flats understanding that our flat is in builder share. Now last month builder absconded and land owner suddenly came to site and said that he is having 40% share in this apartment and whoever bought the flats from that share will not allow to occupy the buyers. Then that time we came to know that they made another MOU in Nov-2015 between builder and land owner which we were not aware about that. That MOU says land onwer has sold all the 40% his share to builder and builder has to pay him one certain amount within 10 months with grase period and if he fails then 40% flats will be in land owner custody till the amount is paid. Now because of these issues the work is stopped. So please can you advice us how we can solve that land owner issue and start the pending work. Nowadays builder is absconding and we are not able to meet him and short out the issues and also unable to start the pending work.