Updated pass, gateway access broke - service asking for credential update but there's no option to?

[olimilo]

I recently updated my password but upon checking our reports in the service, a paginated report that is connected to a SQL server via a gateway no longer worked. I have updated my login on both PBI and PBI Report Builder, republished the paginated report both as a replacement to the old one and a new one for testing but I'm still getting this error when running the paginated report in the service:

A data source used by this report returned an error. A non-serializable exception was encountered 

When running the report via the Report Builder app, it works just fine. I used both these options but neither one worked after republishing to the service:

Upon checking the gateway settings, it said: "Gateway or datasources not reachable" however the gateway is online and working properly as per our admin. When republishing the report to the service, there is a link that says "Update data source credentials" but there is no option for me to do so in the report settings page:

Anyone know a fix for this?

[olimilo · Accepted solution]

This completely flew by me. In the Manage Gateways page, under the Data Sources tab is where I was able to update my credentials:

Special thanks to Weian from the MS Support team who gave me a lead to this.