Omaxe trying to extract more moneythrough unlawful means for possession of flat in Omaxe Grandwood,N

Q: Myself Md. Zeyauddin had purchased a flat in Omaxe Grandwood (Flat No 705,Seventh floor Alpine-C at situated at Sector -93 B of Noida(U.P.)).
I have received the offer for possession of the above said flat vide letter OBPL/N93B/1077 dated 18th June 2011 from Omaxe.
I would like to draw your attention towards an anomaly between the value of the flat as per the Statement of Account attached with the letter offering possession of flat vide letter OBPL/N93B/1077 dated 18th June 2011 and the Allotment letter of the flat which issued in May 2010/Intimation of due installments letter dated 15th Feb 2011/endorsement letter addressed to HDFC Ltd Dated 20th April 2011 allowing HDFC to mortgage the property.
As per the Statement of Account attached with your letter OBPL/N93B/1077,total value of the flat has been stated as Rs. 4767240/- whereas as per the Allotment letter/Intimation of due installments letter dated 15th Feb 2011/endorsement letter addressed to HDFC Ltd Dated 20th April 2011,the