Why are different here2's i2c address and icm20948 address?

Here GPS
1

I connect here2 gps with CubeOrange.
On Mavlink Console, I type command “i2cdetect” and check 0x0C, 0x55.

I connect icm20948 with CubeOrange.
On Mavlink Console, I type command “i2cdetect” and check 0x68.
and, I couldn’t read compass data from icm20948.

I know that here2 gps include icm20948.
So, I think that I can check same address.
why are different here2’s i2c address and icm20948 address?

In conclusion, I want to use icm20948.
How can I use that?