Delay in temple waves and exorbitant interest char

Review On Amarprakash Builders, Chennai

I booked a flat in temple waves on 2014 under the promise that they will deliver the flat between January 2016- March 2016, finally they asked me to collect the keys on March 2019 but after making a late payment fee of 2.35lacs, when I had requested for a complete waiver, they gave me only 35% waiver. I had showed them that the delay was not by me and it was bank that was responsible for it. Their interest calculations are also wrong. In spite of so many mails and reminder they are not responding to my mails since its a deliberate tactics to dishearten the customer and give up their claim. Can anyone suggest me what is the best way to deal with this issue. I have paid all my dues ( 100%) payment 5months back and still waiting for a reply from t

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