rt-ac87u and e3272 problem

[Jufo]

Hi

I have a problem with the router rt-ac87u, modem (e3272) does not work in NDIS (RAS mode works). The following logs:

dmesg:
option 2-2: 1.0: GSM modem (1-port) converter detected
usb 2-2: GSM modem (1-port) converter now attached it ttyUSB0
option 2-2: 1.1: GSM modem (1-port) converter detected
usb 2-2: GSM modem (1-port) converter now attached it ttyUSB1

lsusb:
Bus 001 Device 001: ID 1d6b: 0003
Bus 002 Device 001: ID 1d6b: 0002
Bus 003 Device 001: ID 1d6b: 0001
Bus 002 Device 002: ID 12d1: 1506

I used the command echo -e "AT^NDISDUP=1,1,\"internet\"\r" > /dev/ttyUSB0

The result of the command udhcpc -i usb0 -p /var/run/udhcpc1.pid -s /tmp/udhcpc:
udhcpc: SIOCGIFINDEX: No such device

Best Regards
Robert