TPS65987D: When Battery power low and open my device, than TPS65987D VBUS will supply 5V , and PV_HV1 Output 3.X V

Part Number: TPS65987D

Dear TI, 

I use BQ24610  to charge singe Li-ion battery(3.0V~4.2V Full charge ), and set my device as sink / UFP, 

Set 2 sink PDOs, 

1. 5V/3A

2. 9V/3A

1.if Battery voltage > 3.8V,   open my device and  plug USB-C adapter ,then TPS65987D  VBUS=9V ,PV_HV1= 8.98V to BQ24610 , and  start to charge battery.

2.if Battery voltage < 3.7V,   open my device and   plug USB-C adapter ,then TPS65987D  VBUS=5V,  PV_HV1= 3.1~3.7V to BQ24610 , and  it can't charge battery.

could you help to check it, does there have any setting should be modified from TPS6598X Application customization tool  or  USB PD circuit?

Thank you very much for your help.