No response from USSD utility in CMX50

[granemar]

I was expecting that the USSD utility found in Network → Mobile → Utilities would offer a simple way to check the balance for the active subscription, but it does not seem to work properly.

When pressing SEND for a request, it waits for about a minute before the session times out but no result is presented.

I tried via gsmctl too. Both actions below gives the same behavior as the GUI. No result presented.

# gsmctl -A AT+CUSD=1,"<ussd_code>",15
# OK
# gsmctl -U "<ussd_code>"
# OK

i also noticed that the network connection is lost for a couple of seconds after a request is sent.

The information popup suggest that that “fallback to lower network type” might happen. If this means that this feature relies on connection to CS network (2G/3G) this feature needs to be updated since 2G and 3G is now faced out almost everywhere.

I tested with same SIM card in another device which has the Modem Manager tool (mmcli) available and the USSD request is processed quickly with expected result without breaking 4G/LTE or 5G/NSA connection.

Device: RUTX50
Kernel: 6.6.126
Firmware: RUTX_R_00.07.24
Build: 1309bb0f24
Build date: 2026-07-01 12:35:04

Quectel
RG501Q-EU
Revision: RG501QEUAAR12A11M4G_04.300.04.300

[Vilius]

Hello, @granemar ,

For troubleshooting purposes, we will require more sensitive information from your end, such as the troubleshoot file, which may contain passwords, public IP addresses, serial numbers, and such. To avoid leaking this information, we have sent you a form to fill out, which you will receive in your e-mail inbox that you have registered your account with in the forums. In the **Ticket ID** field of the form, please enter the ID of this thread, which is 20505.

Please let me know once you filled out the form.

Thank you,
V.