How to open more than one cameras?

VIM3
1

My board is khadas vim3, which has 2 usb pots.
But I can’t open more than 2 cameas,even I close one and open another!

khadas@Khadas:~$ cat /sys/class/video4linux/video1/name
HDR Camera
khadas@Khadas:~$ cat /sys/class/video4linux/video2/name
HDR Camera
khadas@Khadas:~$ cat /sys/class/video4linux/video10/name
amlvideo
khadas@Khadas:~$ cat /sys/class/video4linux/video11/name
amlvideo2
khadas@Khadas:~$ cat /sys/class/video4linux/video12/name
amlvideo2
khadas@Khadas:~$ cat /sys/class/video4linux/video13/name
ionvideo
khadas@Khadas:~$ cat /sys/class/video4linux/video10/name
amlvideo

2

Which image you used? And how you test this? We have test 2 USB cameras with guvcview without problem.