Hello, I already have 5 months of this Samsung Galaxy j5 and I have had a problem with it for about 2 days charging with slow charging I tried to unload it to zero and charge but it was still the same and I changed the charger and unloaded it again and it was written that slow charging .
Pay attention to the cable. I do not know if the J5 has a quick charge function, but you can install eg AccuBattery and check the state of mA going from the charger. Sometimes a slightly damaged wire reduces the mA. With a completely almost discharged tel, the current should be at least 900mA.