Sarfasi act and consumer right

Hi, A developer has taken loan for developing a project from Bank A and this builder further open the yet to be completed project for consumers to book by parnering with Bank B to give finance to consumers on the flats of said projects with a scheme of NO EMI till possession. Now Consumer book flat by giving 10% value of project as downpayment and getting into a Tripartite agreement and getting a home loan from Bank B for rest 90%, After few months Possession is delayed, Intrest and EMI which were supposed to be paid by developer is also not paid! Now the loan of consumer which was with Bank B against the said flat becomes NPA and Bank B files case against consumer in DRT under SARFASI act. what should consumer do in such case? If he agrees to pay to bank B its due than he is neither getting refund from developer ( since he is defaulter) nor does he will get possession of his flat as work is haulted and flat is still under construction. also Bank A has also filed SARFASI case against developer for getting the property attach. What is the option available with consumer in such case? Is Bank B not liable, since they had approved loan on underconstruction property which already had loan from some other bank ( Developer had taken loan from Bank A). Kindly suggest course of action for consumer.