Cannot change E3372 settings anymore

Hi!

I’m trying to harness Huawei E3372. I bought it with a hi-link firmware, but flashed it into a stick mode (I need some local devices to be accessed from outside).
Initially it worked fine, I was able to pull “Info” from the modem, change and save its settings, etc. Now, for an unknown reason - I can’t do that. When changed a SIM card, I needed to set a new PIN, but I only saw an error message:
Couldn’t change Interface - no such info channel! (8)

Also, I’m unable to get device “Info”: Couldn’t start - Unable to acquire port! (6)

It’s important to note, that the device is working, transmitting data, etc. (I’m using it to post this).

  • EDIT: some further information:
[admin@MikroTik] > /interface ppp-client print 
Flags: X - disabled, R - running 
 0  R name="ppp-usb-modem" max-mtu=1500 max-mru=1500 mrru=disabled port=usb1 data-channel=0 info-channel=1 apn="internet" pin="****" user="internet" password="internet" profile=default phone="" dial-command="ATDT" modem-init="" null-modem=no dial-on-demand=yes 
      add-default-route=yes default-route-distance=0 use-peer-dns=yes keepalive-timeout=30 allow=pap,chap,mschap1,mschap2

Unable to get info or disable:

[admin@MikroTik] > /interface ppp-client info 0 
failure: Unable to acquire port!

[admin@MikroTik] > /interface ppp-client disable 0     
failure: no such info channel!

… but it’s working somehow!

[admin@MikroTik] > /interface ppp-client monitor 0     
          status: connected
          uptime: 4m37s
        encoding: 
             mtu: 1500
             mru: 1500
   local-address: 10.153.146.97
  remote-address: 0.0.0.0

Of course I’ve tried to reset the router, but it didn’t help.
Then I’ve disconnected USB device and I was able to change setting, so I set new a PIN, attached the modem with a new SIM card, and it’s fully functional again.

[admin@MikroTik] /interface ppp-client> info 0 
       modem-status: ready
         pin-status: no password required
      functionality: full
       manufacturer: huawei
              model: E3372
           revision: 21.180.01.00.00
...
  access-technology: Evolved 3G (LTE)
     signal-strengh: -63 dBm

Don’t know what to think about it… What happened?

Any advice?
Thanks!