Loud speaker not working

After catching my iPhone 6 on fire replacing the battery I decided to try and replace all the parts that weren't working correctly. Right after it caught on fire I cleaned it up, put in a new battery and it seemed to work fine. The loud speaker was a little tinny sounding and the headphone jack didn't work all the time. I then replaced the lightning port headphone jack with a used OEM part off of eBay and that solved that problem. The issue I am now having is that I removed the tinny sounding speaker and replaced it with several other loud speakers but none of them are working and I threw out the old one. I've tried restarting the phone and everything but no luck. I don't understand how it worked with the old one in but no sound at all from the replacement ones. Any ideas?

Still not working after cleaning the contacts. The first lightning port connector and speaker I used was from ifixit and the speaker did not work. I then replaced the ifixit lightning port connector with an OEM one because my cell signal was really bad. That fixed my signal but not the speaker. I then ordered an OEM speaker and put it in and if I would go into settings and turn the volume down in sounds and then try one of the ring tones then I could hear the tone one time at a very low volume. Now that I've disassembled again and tried cleaning I hear no sound.