Sorry I missed this one. It sounds like the batteries died – when the batteries get below a certain threshold the meter will blink quickly to warn of impending doom.
First I would try replacing the batteries, and note that when the meter is reset it sits in bootloader mode for about 10 seconds. This is when the meter is flashing slowly 1sec on 1sec off. If you wait for it to exit the bootloader and connect then, you should be good.
Hope this helps, best