Why my phone doesnt have sound?

I need ur helpppp!!. My phone doesnt hve sound since last week. I already make the volume maximum but it still doesnt have any sound only vibration is working. My father ignore my problem cause he wants me to focus on my exam. but still, my phone is my alarm for me wake up in the morning for school. i cant call anybosy since the sound doesnt working. I already reset my phone but it still not working. Can anybody help me? I have been crying in my room for 2days and i realized that i should try to ask people about this. Thank you fr ur kindness in helping me.