What to do if the builder is not giving the possession of the flat

Dear Experts, I have purchased a property a 1 BHK flat in Completed Project. Municipal Corporation of Pimpri Chinchwad has awarded a Completion Corticate to project. But my flat is not ready to move. The finishing (Painting, electrification) is not done by builder also Water taps are not at place in flat. I opted for Home Loan and Bank inspection person visited property and he has noted his observation as Flat is ready to move (I really don’t know how he has come to this observation as by looking at prima facia the flat is not finished properly). Builder also given demand letter of 100% payment and he said to me that after receiving the 100% disbursement from bank he will do the rest of work and then offer me position to me. I worried that after receiving the full payment he will not do his job properly. My self also not having any base fight with him. If ask bank to disburse only 95% payment will it work and can I then ask builder to finish rest work? Please guide me in this scenario