Recently, I was having problems with my mic on my iPhone X. Siri could not hear me unless my phone is one foot away from my mouth. If I put my phone on my desk, Siri won’t be able to hear or respond when I activate Siri. Even with the dictation keyboard, I’m having problems understanding the words I’m saying if I’m not close to the phone. I immediately thought that maybe I just need to clean the mic located in several areas of my phone with some cloth and can air spray. Unfortunately, it did not fix the issue. I chatted with Apple support and they recommended to reset all settings and if that doesn’t work, do a factory reset. Both I did and still the same issue.
Chatted with Apple support again and they recommended a brush to clean the mic. I grabbed one of my unused toothbrush and I brushed all the locations of the mic (front, side and back). I also did the air spray again. After doing that, it fixed my issue. Siri can now hear me even if my phone is on the table or far away from me. Even the keyboard dictation works perfectly now! Who would have thought that a toothbrush can fix my issue?!
Anyway, I just want to share this with you just in case you guys are having the same issue.
Chatted with Apple support again and they recommended a brush to clean the mic. I grabbed one of my unused toothbrush and I brushed all the locations of the mic (front, side and back). I also did the air spray again. After doing that, it fixed my issue. Siri can now hear me even if my phone is on the table or far away from me. Even the keyboard dictation works perfectly now! Who would have thought that a toothbrush can fix my issue?!

Anyway, I just want to share this with you just in case you guys are having the same issue.