Property related Enquiry

Sir, 12 years back I have purchased a independent house, from a second party, who intern purchased it from the original site allotee from local urban development body. I have followed all the legal formalities and transferred the property in my name ( after taking legal opinion verification of documents etc). Even I have taken bank loan from nationalized bank. Currently I am having the possession of the property. I am also paying regular taxes etc. Now local development bodies were contacting us stating that there were some issues in initial property documents of allotted sites created by involvement of urban development officials. they are claiming that there is a COD enqurey is going on and asked us to submit the documents. Currently Title deed and EC , Property paid taxes, ECity bill every thing is in my name since past 11 and half years. Request to advise if initial two parties ( including urban development authorities) made any goof, then what will be the impact on my current possession.