Object map is invalid, disk utility failed
I ran the disk utility rebooting it with command R -- it says it failed. How do I go about repairing it? I have drive genius and it says to reboot with a drive that I have to erase?
My computer seems to be working fine. I have an iMac 2014 running 10.14.6, 32gb memory, hard drive is almost full.
Thanks!
iMac with Retina 5K display, macOS 10.14