Firmware upgrade problem

I have 2 MyCloud Mirror (Gen 2) drives. I updated the first to firmware 2.40.157 today with no problem. Then I tried to update the second one. After a few minutes the Power light went solid red while the disk1 and 2 lights remained solid blue. After an hour or more with no change and being unable to access the drive I finally removed the power. When I return the power the disk lights are both blue and the power light is flashing. This continues for about 20 minutes after which the power light is solid blue while the two disk drive lights are solid red. No access to the drive.

Any ideas on what is going on and what I should do?