iPhone 4S battery indicator stuck after upgrade to iOS 7

I have just upgraded my iPhone 4S to the new iOS 7 and since then my battery indicator is stucked at 44%. Now regardless how much I charge or how much I use, it is showing the same lbattery level.

Although this get refreshed when I restart the iPhone and it shows the current battery level and then again stucks at the same percentage. This was working fine on iOS 6, but is showing issues after the upgrade.

I have tried to restore it, reset settings by selected Erase All Content and Settings, but still no good, it shows the same level of battery percentage at which it is since last reboot.

Any idea what to do now?