Try wiping the cache partition.
To wipe the cache partition, follow next steps:
Turn off the LG G2.
Press and hold both Volume Up and Volume Down keys at the same time.
Press the Power key only until the phone vibrates once, then release only the Power key.
Continue to hold the Volume up and Volume Down keys until the Android System Recovery screen appears.
Press the Volume Down key to highlight wipe cache partition.
Press the Home(GB only) or Power(ICS only) key to select.
Make sure Reboot System Now is highlighted and press the Home or Powerkey to reboot.
It has lately not kept a charge for very long, so I got a new battery put in, but it didn't help much. The display also flashes at random, or sometimes when texting. Now today it is cutting off voice conversations, and not sending texts. What else could I try? I just got done paying for it.
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