Why is my fast charging works slowly?

[ChronoArc]

Im using s7 edge and its good for a while till i realize my phone isnt charged even when ive leave it for an hour , it says fast charging but its slow, the cable sometimez goes hot and sometimes not

 

[Rukbat]

Have you regularly been using the phone until the battery drops below 40%? If so, the battery is probably shot and has to be replaced. (Lithium batteries are not deep-discharge devices.)

If not, and with the diagnosis that the cable sometimes gets hot, I'd suspect the charging circuitry in the phone (which means a trip to a repair shop).

 

[chanchan05]

^That is too early to happen. While it is a possibility, it's very unlikely to happen for at least a year.

The basic question is, how long exactly does it charge. An S7 Edge on fast charge should take around 1hr30min from zero to full.