Unmounting disk: Couldn't open device.:(~69877)

CPU: i5 7300HQ with Intel HD Graphics 630 GPU: GTX 1050 (disabled) WIFI + Bluetooth: Dual Band Wireless-AC 3165 Ethernet: Realtek Audio: Realtek Keyboard and Trackpad: PS/2 USB 3.0 BIOS: Dell HDD: Toshiba MQ02ABD100H

This error occurs when I try to erase my hdd to install macOS. I noticed in the sidebar that my bootable USB is not showing up as an external device. Any idea on how to fix this?