DC / DC converter Startup problem

When starting at low temperature, when the input voltage is only 3-4V, the voltage at the voltage divider resistance of the undervoltage point is only 0.53V, and the 2V undervoltage opening point of the UVLO has not been passed. That is, when the power supply voltage of the chip LM5027 does not reach the power supply voltage, the output of the PWM chip OUTA has a trigger pulse of about 3-4V about 10ms. At low temperature, the pulse sometimes becomes a continuous long pulse, which causes the MOs tube to open frequently and the module to start short.road.