Betterment charge payment during CMC

[hanamantagoud]

Hi ,

I have bought a site in North Bangalore which comes under erstwhile Byatarayanapura CMC.
Site has A khata for which betterment charge was paid in year 2001 to Byatarayanpura CMC.
Previous owner has given me a old betterment charges receipt .

Couple of weeks back i have an application in BBMP for khata transfer.
Now BBMP guys are telling me that betterment was never paid earlier and betterment paid receipt is fake.
How do i know the betterment paid receipt is fake ? Is anybody having a genuine betterment paid receipt during CMC's ?