I cant factory reset my phone because my touch screen ,sound button and power button are not working

[Blang5014]

Hi

I have an issue with factory reseting my  phone Sony Experia XA (F3211). The power and sound buttons are not working and screen is frozen saying '' Process system is not working ''.I think i got a virus in my phone and i want to factory reset it so the virus is gone. Can someone help me ?