IPhone won't charge?

I've had my iPhone 6s for about a year now, and it won't charge. I've changed the wall outlet, tried three different chargers (all were expensive chargers) and it won't charge. What can I do? Also other day my battery went from 100 to 50 in like one

I don't know what the warranty is on them but it sounds like the battery is shot. And you should use the charger that comes with the phone and not try to leave it on the charger all the time, thats not good for the battery.

Try getting can of air n air out the charger port. Cause even a bit of dust or lint will keep it from charging. If that don't it may be like Dawn said time for a new battery

The battery is bad.