How can I connect my Kotak Mahindra bank account and fix the Error 155?

Thank you for reaching the Community, aamirmalik2305-i.

Let me share some information and make sure you're able to enter your bank transactions in QuickBooks Online.

You should be able to connect your Kotak Mahindra Bank in QuickBooks Online. If not, it means that there' an issue connecting to your bank and we're  working with your FI to resolve this issue. I'd also suggest reaching your financial institution to and request that they allow the connection. For more details about the banking error check out this link: Fix Bank error 155.

As an alternative, you can download a CSV file of your bank transactions and import it in QuickBooks Online. Here's an article for the detailed steps: Manually upload transactions into QuickBooks Online.

I'm adding this resource to help you categorize and match online bank transactions in QuickBooks Online.

Please reach us back if you still need further assistance about other banking concern. I'd be glad to help. Take care and have a nice day!