Can't update the app registration for my teams app

I need to change the EntraID app registration manifest in order to change the signInAudience property.

When I try to save the manifest, I get the following error:
"Failed to update XXX application. Error detail: No other properties may be modified when certification properties are being modified."

Which certification is meant here? The last update of the teams app referencing the app registration was months ago so there shouldn't be an ongoing certification at the moment.