Bank refused Court Affidavit

Respected experts, My late father invested some amount in the Golden Forests in my sister's nick name Miss Mani long back. Now after so many years she has received a cheque for Rs 2100 in the name Miss Mani. She holds a bank account in her actual name of Miss Manasri. She went to her bank to deposit the cheque with a Court Affidavit sworn by her that Miss Mani and Miss Manasri is same and one person. The bank manager straight way refused to accept the cheque and the Court Affidavit. Kindly inform as to whether the bank manager was right in refusing the Court Affidavit? Kindly also inform what legal action can be taken if the manager was wrong. Regards.