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LTM4653 input and output short to ground


I have designed a power supply module using

1> LTC3889 - output-1=24vdc, output-2=24vd. and 

2> LTM4653 output-3 = 48vdc

Input voltage = 50VDC.

Problem: LTM4653 input and output get short to ground( mosfet ) when ever i switch on LTC3889 using RUN pin.

LTM4653 = switching frequency 1.2 Mhz. design is exactly copied from

i feel cause of problem might be 

1> FSET Resistor placed near to LTC3889 output inductor.

2> CLKIN pin floating connected to TP-testpoint using resistor.

let me known if any additional data is required to solve this problem.