2 Phase operation in LTC7840 not working

I am designing a SEPIC/ BOOST Converter with LTC7840. To keep the input current waveform form battery steady i am trying to use 2 phase operation feature of LTC7840, unfortunately it is not working as expected. Ideally the two channels should be with 180Degree out of phase with each other with same duty cycle when circuit component son both channels are same, i.e. circuit of channel 2 is copy of circuit of channel 1 and PCB layout is also symmetric. I am trying to get the output of 60V and expected power output id 150W. But the system becomes unstable for power more than 15W and moves into DCM. Besides this though the duty cycle of both channels to be same but, in my testing it is found that channel turns off as soon as Channel 1 turns off hence a very small duty cycle as compared to channel 1.

Also the explanation of its Hiccup mode mentioned in the datasheet is not  clear to me, Could you please provide nay document on the Hiccup mode ?