RBM33 V7.5 won't see LTE device

Hello,
I’m trying to work with LTE modem (MBIM) on my RBM33G V7.5beta5 (testing)
using EC25-AU modem
I have enter the correct command :

[admin@RouterOS] > /interface/ppp-client/at-chat ppp-out1 
input: AT+QCFG="usbnet"?
  output: AT+QCFG="usbnet"?
+QCFG: "usbnet",2

OK

reboot the router
but I still see it as ppp-out with 4 ports

do I need to do something else?

Thanks ,