i put my phone on charging but charging did not start i tried three times like this but it did not turn on but at fourth time when i again reconnect charging cord again it did not turn on unless untill i swipe screen and unlock my phone and as soon a

i put my phone on charging but charging did not start i tried three times like this but it did not turn on but at fourth time when i again reconnect charging cord again it did not turn on unless untill i swipe screen and unlock my phone and as soon as i unlock my phone with passcode charging of phone started so is that something or problem with hardware of the phone or what else it is as i notice this problem 1st time only in a year and now whenever i connect my phone to charging it is starting normally like it was used to before