Samsung A20 Hard Reset

I just ordered a new A20 since my old one is having major issues. It can't detect my SIM card (checked that the SIM is working on a different phone), it can't connect to WiFi, and it can't connect bluetooth either. It also can't accept a tethered mobile hotspot as well as it can't connect to my PC via Kies 3 to update or reset. Since I can't connect to the internet, I can't do a factory reset from the settings either.

So here's the predicament as above is just stating what I've tried and what isn't working. I'm trying to hard reset by holding down the volume up button and the power button. Literally nothing happens when I hold down those buttons. Before asking, I have also reset/power down and let it rest many many times.
Is there any final solution to hard reset/factory reset my phone before I send it back?