Why is my 3DS Not Charging?

I recently took out my 3DS and upon trying to charge it, the charging light would not appear. I assumed that the system's charger port was broken, which I researched could be a couple different issues: the two pins on the inside of the port could have been bent, and would need to be bent back into shape to get it working. That didn't do it, so I opened the system up to see if there were any broken connections to the port. They were all in tact, but I applied extra solder to each of them just in case. It didn't fix it. Here are some pictures:

Are there any other reasons the system wont charge/the charging light wont appear? Any fixes?

Thanks in Advance