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Hi there,

I am new here and hope on right place to ask for help.
At the moment I am trying to send USSD request to mobile operator and cannot get response from operator.

When I use standard GSM phone I send *122# as USSD message and in a second I have answer with balance on my prepaid account.

Now, trying the same with AT commands...

I had two scenarios:

1) Using AT commands and Hyperterminal
AT+CUSD=1,"*122#",15 (my request)
OK (response from modem)
In futher, nothing happen. Not as response in HyperTerminal nor as an SMS message which I can check using AT+CMGL="all"

2) Using AT commands in "ActiveXperts Mobile Messaging Toolkit" software
As a response from this software I have "30115: No more data available in receive buffer"
But, here is a log file from this software:
[13:37:13] Mobile Messaging Toolkit: [AxMmCtl.dll 6.0.4.20119 (x86)]
[13:37:13] Open [HUAWEI Mobile Connect - 3G Modem #3] as TAPI
[13:37:13] Sending command: [ATV1]
[13:37:13] Read response: [OK]
[13:37:13] Sending command: [AT+CPIN?]
[13:37:13] Read response: [+CPIN: READY]
[13:37:13] Read response: [OK]
[13:37:13] Sending command: [ATE0]
[13:37:13] Read response: [OK]
[13:37:13] Waiting for the device to register on the GSM network
[13:37:13] Sending command: [AT+CREG?]
[13:37:13] Read response: [+CREG: 0,1]
[13:37:13] Read response: [OK]
[13:37:13] Device is registered
[13:37:13] Sending command: [AT+CGMI]
[13:37:13] Read response: [huawei]
[13:37:13] Read response: [OK]
[13:37:13] Sending command: [AT+CGMM]
[13:37:14] Read response: [E220]
[13:37:14] Read response: [OK]
[13:37:14] Sending command: [AT+CGMR]
[13:37:14] Read response: [11.117.10.03.99]
[13:37:14] Read response: [OK]
[13:37:14] Sending command: [AT+CGSN]
[13:37:14] Read response: [356635025784417]
[13:37:14] Read response: [OK]
[13:37:14] Sending command: [AT+CMEE=1]
[13:37:14] Read response: [OK]
[13:37:14] Sending command: [AT+CSMS?]
[13:37:14] Read response: [+CSMS: 0,1,1,1]
[13:37:14] Read response: [OK]
[13:37:14] Can send: [YES]; Can receive [YES]
[13:37:14] Sending command: [AT+CNMI=?]
[13:37:14] Read response: [+CNMI: (0,1,2),(0,1,2,3),(0,2),(0,1,2),(0,1)]
[13:37:14] Read response: [OK]
[13:37:14] Sending command: [AT+CNMI=0,0,0,2,0]
[13:37:14] Read response: [OK]
[13:37:14] Supports receiving status reports: [YES]
[13:37:14] Sending command: [AT+CMGF=?]
[13:37:14] Read response: [+CMGF: (0-1)]
[13:37:14] Read response: [OK]
[13:37:14] Sending command: [AT+CMGF=0]
[13:37:14] Read response: [OK]
[13:37:14] Message format set to: [GSM_MESSAGEFORMAT_PDU]
[13:37:14] Prefix SMSC info set to: [GSM_PREFIXSMSC_ENABLED]
[13:37:14] Sending command: [AT+CUSD=1,"AT+CUSD=1,"*122#",15",15]
[13:37:15] Read response: [OK]
[13:37:25] Connection closed

As it can be seen here "CONNECTION CLOSED". Why ? Is it reason why I don't get response with balance from mobile operator.

Is there any other reason for not having response (on modem) as on mobile phone?

As far as I have understood response on USSD can be USSD response or SMS message. If I understood it well, I should have in Hyper Terminal this USSD response ???