Problem using my phone (I can't use my earphones)?

I'm using a Lenovo K900 any help? I tried different kinds of earphones already but the music is always on loudspeaker not on the plug And it kinda sucks already even the lenovo earplug won't work any resolution before I bring my phone to the center points to the solution that'll definitely work

How about you make sure the wires aren't tangled?

Check if there's no something stuck in your headphone jack.
if it won't work then you should see your service center.

When your inserting the plug in the hole don't put it full inside. It does happen to my laptop also some headphones work some don't so i put the plug half way and shake it then it start to work. Please remberer when you insert your plug in the hole there's a switch init which switches off the loudspeaker. So check if this damaged or not