If your SIM card is not working, please check the following:

• Do you have enough credit?
  Check your credit with *123# call key and top up if necessary.
• Do you have reception?
  yallo/Sunrise should appear on your screen. Otherwise we recommend that you check if you have network reception at your location by performing a manual network scan in the settings.
• Did you insert your SIM card correctly into your cell phone?
  Please make sure that your yallo SIM card is inserted correctly into your cell phone.
• Is your cell phone SIM lock locked?
  The info message "SIM Lock Lock" on your device means that your cell phone is only unlocked for a certain network operator. This is usually the operator you bought the device from. SIM cards from other providers are not accepted and can only be used in the device after the SIM lock is removed.
• Is your SIM card deactivated?
  If your prepaid SIM card remains unused for 12 months (i.e. you have not sent any SMS, made any calls, surfed etc.), yallo is entitled to block your mobile phone connection without notice. If you do not request a reconnection after a further 6 months, yallo is entitled to terminate the contract and to reclaim and reassign the corresponding number. Refunds of top-ups or account balances are excluded thereafter.