HDFC Bank — ACH Mandate registration

I have taken loan from HDFC bank. Last week I received a text stating that I need to complete my Mandate registration. I have completed the registration and received confirmation over text but today again I received a text from HDFC stating

Dear Customer, Your ACH mandate form submitted towards repayment of your Loan No. Xxxxxxxx with HDFC Bank has been returned by STANDARD CHARTERED BANK due to " Drawers signature differs ".

How am I suppose to know whether my mandate registration was successful or not although I have a confirmation that it is successful but still I am receiving such text from HDFC.