SubscriptionUpdateConstraints Error from webRTC

[krishna__venkata]

Hello Team,
we tried to update for Subscription Constraints for video using OWTConferenceSubscriptionUpdateOptions. We are getting error as 

Error Domain=com.intel.webrtc Code=3000 "Negative acknowledgment from server." UserInfo={NSLocalizedDescription=Negative acknowledgment from server.} 

How to resolve this error, any help will be appreciated.

Thanks

[krishna__venkata]

Any update for this