File complaint against builder before consumer forum or RERA and seek orders to direct builder to refund your money with interest 

2) builder is bound to pay interest  as there is delay on his part in completion of project 

check your agreement

does it have any clause which says that in the event of cancellation the builder will refund the money, however without any interest?

to my mind if the purchaser cancels the units then he is liable to pay the cancellation fee as agreed in the contract/agreement

in your case the builder is not charging that which amounts to a novation of contract 

assuming there is a provision for charging cancellation fee when the purchaser cancels the units for no fault of the builder then the purchaser cannot require the builder to pay interest on the moneys so far paid by him

interest is paid only when the builder breaches the contract by not handing over the possession on the agreed date as stated in the contract 

As the default is on the part of builder with any consent from RERA there is no iota of doubt that he has pay interest by way of penalty on the advance paid to him. First to collect the advance paid and then file a consumer complaint against him in District Consumer Commission under new Consumer Protection Act, 2019. In spite of any undertaking forced by builder not to claim interest, you can still claim the interest as any such undertaking amounts unfair contract under Section 2 (46). You can also claim that just to get refund, you gave such undertaking under financial pressure. You will get interest with cost of complaint an lawyer's fee.

Hi, You can cancel the allotment as a delay in the project and you can lodge complaint either in RERA or consumer court for refund of the amount with interest. Further, the Builder can't charge 15% as cancellation charges and it was a un-ethical practice.

- As per the RERA Act, if the builder is delaying in construction & delay in possession, then the builder will have to pay 10% interest on the value of the property for delayed possession of flats.

- Further, if builder fails to delivers the possession of the flat to you on time, then you can cancel the agreement due to his fault and you are liable to get full refund of paid amount with 10 percent interest. 

- Further, if you get the possession of the said flat lately, then also you can claim 10% compensation from the builder. 

- Hence , you can claim the interest for 4 years and also compensation for harassment caused due to delay in the project.

- You can send a legal notice for getting interest and compensation , and if no refund then file a compliant before the Consumer forum. 

Dear client,  The builder is liable to pay you the entire amount if the agreement is not registered
Legally, the developer cannot deduct any money out of the advance payment you have made for the booking till the time a builder-buyer agreement is made and registered with the sub-registrar.

If the builder has agreed to refund the full amount owing to the cancellation of booking and after the realisation of entire amount you may decide to initiate legal proceedings against the builder demanding interest for the amount refunded.  

You can approach RERA and institute legal proceedings for this, but until then you may wait patiently because the builder may not honor his commitment of refund of the booking amount if he senses that you are initiating legal proceedings and may take shelter under the roof of pending litigation to trouble and harass you more. 

If it's getting resolved without interest you can settle the same.For interest you need to approach consumer court Or rera

You have to sale brochure which was given at the time of purchasing the flat.

Kindly check termination clause mentioned in the agreement plus any interest clause.

Regarding interest in adavance payment you can ask in the RERA forum. Once the order is passed by RERA builder has to give you your advance payment along with interest.