Reboot unsuccessful :(

[Manikapoako]

Hi, i have tried holding the home,power and volume up button to reboot my samsung s3 but it didn't work. And also my problem is,its hard for me to open the power button because the cover/button is broken/gone. Hope someone could help me on this. Im sick on using my phone on safe mode can't use apps

 

[nahoku]

Remove and replace the battery... that'll restart the phone.