I followed the installation process from the kali linux docs but I've run into a problem: when I try to do the partition of the hard drive an error appears saying: "Partition(s) 2 on dev/sda have been written, but we have been unable to inform the kernel of the change, probably because it/they are in use. As a result, the old partition(s) will remain in use. You should reboot before making any further changes".
There are to options: ignore or cancel

What should I do?