iphone 6 battery

My phone is up to date on the updates, but the battery issues still remain. The phone will jump from 90 percent to 80 within seconds and continue until it gets to about 30 percent, then it will die. Plus, the phone does not charge unless its tilted a certain way - there's nothing in the charging port, I've checked - and the charge will just fall out if I pick up or move the phone..