wowza A key frame has not been received & stream record duration issue.

I am getting below error into the wowza Stream Engine log. anyone here who helping me out to fix this error and also tell me reason why this error is occurs.

CupertinoPacketHandler.chunk [live/definst/stream1] A key frame has not been received in this audio and video stream for: 4254426.257 seconds, which is over the max chunk duration of: 50.0 seconds. Restarting packetizer for stream: stream1.

Duration Issue :

When I record the stream it was record perfectly but some of video get wrong video duration. like suppose video duration contains 2 min. it is showing in vlc media player 11 hour. so how can fix this issue.