Well, that makes things difficult.
The next thing to try would be to get the back-up BIOS to kick in. This can take several attempts so don't give up to quickly if it doesn't work the first few tries. Timing is important and it can sometimes feel like it isn't going to work at all.
1. Shut your PC down. Remove the power cord press the power on button on the PC case a couple of times.
2. Reconnect the Power cord then press the power button on the PC case until the PC starts. As soon as the PC starts pull the power lead or turn off the power so that the PC shuts down.
3. Re connect the Power and press the power button again, your backup BIOS should kick in now and should re-flash the main BIOS.
4. When the Backup BIOS has finished copying to the main BIOS chip, shutdown the PC, wait 30 seconds the restart. Hopefully, you should now be able to get into the BIOS.