Bank Of India — my registered mail id was wrongly updated by bank

My registered mail id was wrongly updated by bank in my account. Now when i am trying to change it online via internet banking service i am not allowed to do so. An error message displays saying please contact your branch. After that i tried calling your customer care number several times but before call being transferred to your executive it gets disconnected with a thank you for calling boi message. I need to update my registered mail id urgently. Please do the needful to resolve my issue before i escalate it to higher authorities \ nodal officer \ banking ombudsmen.

Regards,
Zahir chamadiya
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