My iPhone is plugged in but it won't charge

It could be a number of things.

• It could be that there is lint in the port. But no, you don't need to be a professional to clean it out. Under a bright light, with a magnifier, if you have one, use a non-conductive tool such as a toothpick to carefully remove any pocket lint or other debris that's gotten smashed into the back of the port.
• It could be a bad cable. Have you tried a different one? Have you tried this cable on a different phone?
• It could be a bad adapter. Have you tried a different one? Have you tried plugging the phone into your computer?
• It could be a bad wall plug. Have you tried plugging it in somewhere else?
• Or, it could be that there is something wrong with the port itself. Do you have access to a wireless charger you can try? If it works when you use a wireless charger, that would indicate there is a problem with the port. If it still doesn't, the issue may be with something else in the phone.

See also:

If your iPhone or iPod touch won't charge - Apple Support

I had same problem so I changed the power adapter fixed problem :)

I had the same problem figured it out it was the power adapter power adapter is the part that connects to your wall

Your cell phone’s plug is full of debris and needs a professional clean out, so you can use the cell’s plug to charge your phone.