No output from Header/Payload Demux block in rx_ofdm example


I am working on ofdm examples. In rx_ofdm.grc, I am able to receive the
data but I don’t see any output from the Header/Payload Demux block. I
made a plot of the received signal after Schimdl & Cox Ofdm Sync. block
and was able to detect the peaks of the signal that indicate the start
of the frame. Can anyone tell me what could be the problem?

I am using gnuradio 3.7.1.

Murali Kris