Why my phone won't charge anymore?

So my phone is Lenovo A6000 plus, it started just yesterday when my battery came down to 20 %, I went for my charger to charge my phone and I found that my phone wasn't charging anymore, I tried different chargers then on power bank too but it won't charge, After reading one of your solution I took out the battery and then​ charged my phone there after I charged my phone again after putting the battery it did charged. But again when my phone's battery came down I have to redo this things again and again..Is there any total resolution!?