Do the maintenance mode by removing or moving the cmos jumper. Follow the procedure given in your mb guide.
Hi, there is an easier way to enter BIOS if F2 doesn't work anymore.
If the option » USB Optimization « has been changed from Disabled to Enabled, F2 will no longer work during POST.
BIOS ► System Setup ► Boot ► Fast Boot ►
- General Optimization
- USB Optimization ◄──
- Video Optimization
» If enabled, USB devices (keyboard and drives) will not be available until after OS boot, but BIOS will boot faster. If disabled, USB devices will be available before OS boot, but BIOS will boot slower. This question does not affect USB capabilities after OS boot. In order to disable Fast Boot without entering BIOS Setup: Power down the system, then hold down the power button until the system beeps. «
It worked for me.