1. The delay in making payment by the Bank for and on your behalf was due non compliance of certain contitions by the Developer as detected by the lending Bank,
2. Collect all the letters/documents exchanged by and between the Bank and the developer in this regard,
3. These will stand as very good evidence to prove against the Developer that delay in making payment by the Bank was on account of his fault,
4. If the interest is of not substantial amount, it will be prudent on your part to pay the same under protest, take possession of the flat, get the same registered in your name and then file a complaint case before the local District Consumet Dispute Redressal Forum alleging deficiency in service and unfair business practice claiming refund of the said amount paid, intrest, damage and cost.