Some YUPHORIA devices gives problem after updating to 12.1 so you need to re flash the device to previous version 12.0 below are the steps for flashing YUPHORIA device.
1. Before following below steps please take the backup of your device data as your entire phone data will be wiped. This process may take some 40-45 mins for full boot up.
2. Make sure that your phone has enough battery power for the installation process (and the download too, if set to manual). The update process will work best if your phone has at least half of its battery life available, or if you plug it into an outlet during the installation process.
3. Follow the CM12S OTA flashing process for lollipop update with incremental OTA update mentioned below to resolve the issuewith the new updates:
Steps to flash factory image:
1. Download the factory image Fastboot package from http://builds.cyngn.com/
factory/lettuce/cm-12.0- YNG1TBS2P2-lettuce-signed- fastboot.zip
2. Extract the contents of the Fastboot package into a folder.
3. Download this flashing tools package from
factory-image-flash-tools/ archive/yuphoria-lollipop- windows-flashtools.zip
4. Extract the contents of the flashing tools zip into the same folder
5. To make sure, check that system.img, boot.img etc files are in the same folder as flash-all.bat, fastboot.exe etc
6. Connect your phone in Fastboot mode, steps for which are: –
a. Power off your phone
b. Press and hold the Volume Up key
c. With the Volume Up key, connect the phone to your PC/Laptop with USB cable
d. You can let go off the Volume Up key when Fastboot Mode is displayed on the screen
7. Run flash-all.bat by double clicking on it.
8. A command window will open and flashing procedure will start
9. DO NOT disconnect the device during flashing procedure
10. The command window will close after the flashing process is over.
11. Disconnect the USB cable, and boot the phone normally by long pressing the Power button.