FIX USSD on iPhone 4s and iPhone 5

1. Go to Cydia 

2. Add repository (apt.chinasnow.net) 

3. Install "CommCenter patch for iOS 7"

4. Run "iFile" and go at /System/Library/Carrier Bundles/iPhone/Default.bundle/carrier.plst

5. Click on carrier.plst and select "Viewer PList" 

6. Flip through down and find the item SupportsSupplementaryServicesOver3GPP (turned it off) 

7. Turn it "On" and click "Finish" 

8. Reboot the device. 

9. Now working USSD requests.