Ok this may sound cavalier, but I had to use drastic measures as I am too lazy to send my phone away. The problem that I found was the headphone jack was not touching the contacts within it.
Step one- waste 6 hours tearing the phone down cleaning everything
Step two- reset (don’t because I lost EVERYTHING and that doesn’t help anything)
Step three- shove aluminium foil down the jack to try and get contact
Step four last step- I do not recommend this, I spat saliva down the headphone jack to allow the electrical current to contact the necessary elements………..Worked straight away. (i would recomend contact cleaner)
Enjoy!!! Most frustrating thing ever