Getting error while updating an active subscription

[rahulrmishra]

I have created a subscription it is in active state and I want to update the quantity of it. The API is in test mode.

The API gives an error
{ "error": { "code": "BAD_REQUEST_ERROR", "description": "Can't update subscription immediately when card mandate is applicable" } }

What should be done to solve this error?

[trulymittal]

I am also getting the same error when updating the plan (both plan in same currency).