Why this happened with iphone battery?
Ok i never faced this issue before,
 When i plugged in charger in morning it shown "plug" sign where it should show "lighting thunder" sign.
 I plugged out & again plugged in and shown "lighting thunder" sign & started charging.
 After reaching 92 percent i noticed battery percent is not increasing,
 I switched off/on
 It shown me battery percent 96 percent,
 Again above issue started it shown "plug in" sign.
 Then i discharged it to 15 percent and plugged in charger,
 Now its charging normally as before,
 Please tell where is actual problem,
 I have noticed that battery drainage is well as it was before,
 But why it didn't charged to 100 percent.
 I add i plug in charger always when its above 45 percent, i mean i never fully discharged and recharged it.