AT+CUSD doesn't get balance

Question

I have a DataNet GSM Modem (HUAWEI Mobile Broadband E173). I want to get balance with USSD code *141*1# but unfortunately I don't get any result.I get just OK in response.

I read these posts and many others: Error on checking balance via USSD I have tried IRA and GSM and UCS2 but no result. how to get balance by USSD commands? My port is selected correctly because other commands work properly AT command - USSD I test with 15 at the end and without that

My situation is as below:

    AT+CSCS?
    +CSCS: "GSM"
    AT+CUSD=1,"*141*1#"
    ERROR
    AT+CUSD=1,"AA182DA68A8D1A",15
   OK

I should be able get balance in result but I just get OK.

Answer 1

I could solve the problem. The port I have selected was wrong. My modem had 3 port, COM38, COM39 and COM 40. I have used COM38 but when I used COM40 the AT+CUSD=1,"*141*1#" worked.