Q: my iphone6 specker not working

Any chance of a little more information ?

You do realise the iPhone only has one external speaker ,on the right when looking at front of iP6

Get help with hardware features on your iPhone, iPad, and iPod touch - Apple Support

If you hear no sound or distorted sound from your iPhone, iPad, or iPod touch speaker - Apple Support

Hi Home screen swipe up control panel check halfmoon do not Disturb is not on. Check mute button. Cheers Brian

Try plugging and unplugging your headphones into the jack.  This has happened to me before, the phone gets a little dirt or moisture in the jack and then it thinks the headphones are plugged in causing external speakers not to work.  Just happened to me this morning, I had the phone in bathroom with me while I was showering because I was expecting a call.  A little later I tried to play a video and viola, no sound.  Plugged and unplugged my headphones and everything is fine now.  Best of luck.