My one side of headphone not working

My one side of headphone not working
My earphones were very nice but nowadays they are irritating me. Left side of my earphone is not working at all I tried to fix but still not working. Please tell me what to do

ANSWERS:

"New one cost about $12 now and it might not be worth the hassle of trying to fix the old ones.

ebay/itm/Genuine-Apple-M..."