Commission of Oats Affidavit Invalidated By Experian

I have been trying to enquire about wrong/*****ulent account on my credit profile, I sent two Affidavits already claiming that I do not know Brother Finance account and both claims have been declined due to the fact that the affidavits did not have Commission of oats stamp while in the second instance I asked the police to ensure they use the correct affidavit with commission of oats stamp and they did that but still my dispute was invalidated by Experian Up and when I went to police station for the 3rd time they said, the affidavit given to me the second time had a commission of oats stamp and could not give me a different one. What to do now?