Phone not charging properly

So I’ve bought 2 new chargers in the last 3 weeks and both have quit working on me. But my wireless charging pad will charge it every time I put my phone on it. Why is that? I did notice when I plugged in the old cord it gave a little spark from the charge port on my I phone and then it quit working. So I bought a new charging cord and it charged for maybe 20 minutes and now it quit. Could it be the charging block in my truck I’m using, I noticed it was warm. And that’s the only time it’s doing it is in my truck that I’m aware of because when I’m home I use the pad.