Why 0.5 doesn’t work ?

I’m assuming you are asking about the 0.5 camera lens. Is that correct? We’d like to help if we can but need more information. Please reply, telling us:

• The name of your device (iPhone? iPad? Which model?) and its iOS or OS version.
• Offer as many details as possible about the problem. What were you doing or tryin to do ? What happened? 
• Did your device show an error message? Did it include instructions? If so, what was the message and did you follow their directions? 
• List any trouble shooting steps you have already tried.