Sometimes battery won't properly charge

My iPhone 5 started having this problem one day when the battery percentage was stuck on the same percent for an hour. When I powered off my phone and powered it on, the battery percentage increased. After that, my phone will say it's charging when plugged into the wall but the battery percent will decrease. I have tried different adapters/cables and only a few will work. I am currently using an Insignia charge cable and an Apple adapter. Only sometimes, it will work and I have tried plugging my charger onto different outlets and no luck. I think I found a solution to the issue but it's annoying. I think when I power off my phone for a few/couple of hours, the phone will charge and the battery percent will increase. That was working fine until this morning. The battery percent will increase but be stuck at a certain percent, and when I power off and turn it on again, it increases. But afterwards, the battery percent will still decrease after it's still trying to charge. I don't know what is the issue and the possible steps I need to take in solving this issue.