Bad service and customer complaint

I bought a new cellular phone from the grassy park pep stores on tuesday 02/10/2018. I bought because my one broke and i had to replace it because i use it for my small business. Last night i decided to plug in the earphones to listen to the radio, but it didnt want to work. So i plugged in my old ones and it also didnt want to work. I then took it back to the store to show them that its not working, only to be told by the person that helped me on tuesday, that it looks like the phone was open on the front of the phone. And that someone forcefully pulled out the earphones. Since im the only only one using the phone, then she must mean that i did what she said. Why would i want to open up the phone??? For what reason must i do something like that to a brand new phone. Hope someone from Pep could please contact me as im very upset about this lady accusing me of something i didnt do