Your mobile phone hasn't been correctly set up for Internet
Possible cause 8 of 9:
If you're trying to access the Internet using the mobile network, you need to set up your mobile phone correctly for Internet.
What you need to do:
The Internet connection can be used for many functions in your mobile phone, such as receiving e-mails and installing apps. You'll be able to access the Internet as soon as you've inserted your SIM card into your mobile phone. If this isn't the case, you can set up your mobile phone for Internet manually.
Find "Mobile Data Network"
Press Mobile Data Network.
Enter the APN
Press "APN" below "PERSONAL HOTSPOT" and key in gprs.swisscom.ch
Return to the Home screen
Press the Home key to end the session and return to the Home screen.