No Feedback from shop or LG at all. Paid for 4 month without using accesary at all

Good day I bought a LG cellphone on contract 2 April and took the headphone with the accesaries back as it was faulty. I went to the shop almost 6 times and no-one ever phone me back as they said the problem is with LG but I paid my installment aswell as my insurance. Why cant they gave me from the shop as it was 3 days and I never use the headphones at all. They take my number everytime but no one come back to me. Can I take my phone back and stop my premium till I got the Headphones.