LM5069: lm5069上电无法正常启动

Part Number: LM5069

Hello, I have a question to ask. We use the LM5069 chip for power control on our board. When powered on, the ULVO pin will first be pulled up (following the power supply), then the control signal will pull the UVLO down and then the control signal will be released, and then the UVLO pulled up again(As shown in the waveform below),At this time, LM5069 cannot turn on the mosfet. If ULVO is directly pulled down and then the control signal is released ,the LM5069 can turn on the mosfet, there will be output. I would like to ask what is causing this question.

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