Can't Downgrade iPhone 4s iOS 8.3 to iOS 7.1.2

Hi, Once I updated my iPhone 4s from 7.1.1 to 8.3, I downloaded 7.1.2 when I want to downgrade it I tried it in Recovery and Un-Recovery mode but it gives me a code: 3194 When I click this it goes me to this site and says "If iTunes can’t communicate with the update server, you may see one of these messages.

Error 17
Error 1639
Errors 3000-3020
Error 3194
Errors 3100-3999
This device isn't eligible for the requested build
If you see one of these messages and need help updating or restoring your iOS device, install the latest version of iTunes and try to update or restore again. If you need more help, follow these steps."
Please help me!