Bar 30 Pressure Sensor from ArduSub Firmware 3.4.1

Bar 30 Pressure Sensor does not work.
So, in Depth hold mode, the following message appears.
“Depth hold requires external pressure sensor”
The tried method is to change the GND_EXT_BUS parameter value from disable to 1
I tried, but it did not change.
There is only one SCALED_PRESSURE.
Currently the QGC version is 3.2.1 firmware is 3.4.1.
OS is win8.1
help me

What autopilot are you using?
Did you reboot the autopilot after changing the GND_EXT_BUS parameter?

Thank you Jacob
Pixhawk 1.
yes rebot
The value of GND_PRIMARY reverts to “FirstBaro” after rebooting