Consumer Redressal

I was allotted a govt. flat in 1974. The copy of the allotment letter along with the first receipt issued by the WB Govt is available. Monthly rent was collected till May 2015 and receipt has been issued for the said month. However, I have been informed that the said flat belongs to one Mr. Pulin Behari Ghosh. Their internal records also show that they have changed the name internally. I am 84 years old and am an heart patient. Yet I have personally visited the New Secretariat and have submitted a written application to the Estate Manager. I have also submitted a letter through my lawyer but have received no response from the Estate Manager till date. I do not know how to solve the issue. After 41 years I am being told that the said flat belongs to someone else. Please help me in this regard. All original documents are available with me. Looking forward to your advise in this regard for which I shall remain obliged. Thanking you.