Drive not accessible after idle

I purchased a G-Technology 6TB G-Drive and connected to a brand new HP computer running Windows 10 professional. It is connected directly to the computer using a USB 3.1 cord that came with the drive. I uploaded 2 TB of photos and backed it up using Second Copy to another drive. No problems. The first time I went to edit photos a few hours later they were not accessible in Lightroom or Bridge. I could see the drive and all folders in Windows Explorer, but when I tried to open a folder I get an I/O device error. If I restart the computer the drive works immediately afterwards. While technically this is a fix, I don’t want to have to keep restarting the computer multiple times a day just to use this drive. I am thinking about returning it.