Failed to set session description on WebRTC

Question

I set the remote description, callback didSetSessionDescriptionWithError got hit, & showing the error :

- (void)processAnswer:(NSString *)sdpAnswer connectionId:(NSString *)connectionId {
    //NSParameterAssert(sdpAnswer);
    NSParameterAssert(connectionId);

    NBMPeerConnection *connection = self.connectionMap[connectionId];
    __block __weak RTCPeerConnection* peerConnection = connection.peerConnection;
    RTCSessionDescription *description = [[RTCSessionDescription alloc] initWithType:RTCSdpTypeAnswer sdp:sdpAnswer];
   [connection.peerConnection setRemoteDescription:description completionHandler:^(NSError * _Nullable error) {
    [self peerConnection:peerConnection didSetSessionDescriptionWithError:error];
}];
}

after call getting this error.

Error Domain=org.webrtc.RTCPeerConnection Code=-1 "SessionDescription is NULL."

Answer 1

I had faced the same error and fixed it by adding "\n" to the end of the of the Offer string. Hope this helps.