I plug regular headphones into jack it shows headphones on my bar can hear person talking they cannot hear me why does this happen how can I fix samsung galaxy note 2
This gogorapid link provides some things to try. Check if the issue is fixed after each of these.
Remove the battery from your phone for 30 seconds and then re-insert it before powering the device back on.
Use an app such as Smart Voice Recorder to record a short audio clip. Then replay the clip. If you can hear the sound clearly, it means that the microphone is working fine.
Factory reset your device but be aware that this will wipe all user data such as your contacts, photos, app data, etc. Make sure you backup first.
If the problem persists, it means that the microphone is damaged. You should take your device to a repair shop to get it fixed or replaced.