Samsung Galaxy A70 wont turn on

My Samsung Galaxy A70 Doesn’t turn on. when I try the steps on how to reboot my phone the logo only blip and turn black again. i already repeatedly hold the volume down key and the power key but still the logo only blip a second and turn back into totally black screen. i almost forgot when i surrender rebooting my phone and put it in the table because nothing happens every time i hold the key buttons to reboot after an hour the ringtone sound and also vibrate but the screen is still totally black. what should I do to make it turn on?. thank you so much for the answer..