Packets not being decoded in gnuradio 3.6 but was decoded in 3.4 and 3.5

I have the attached codes which were working and the
uhd_cc2420_rxtest.py was decoding packets albeit with high error rate. I
upgraded to gnuradio 3.6 and had to change a few commands like changing
packet_utils to digital and clock_clock_recovery_mm_ff to
digital_clock_recovery_mm_ff.
Both codes are executing without errors and I can see that packets are
being sent using an independent spectrum analyser. Yet I am not
receiving any packets from uhd_cc2420_rxtest.py.

Is there any change that I need to do to at least get a few packets
irrespective of the error rate?

H.E. Baidoo-Williams
GRA, University of Iowa