Had the "spoiler raised / blinking red light on switch / spoiler would not retract" problem last night.

I decided to try cleaning the latch first with compressed air. (WD-40 might also work.)

After cleaning and re-latching the hatch I was able to retract the spoiler via the switch.

I cannot confirm that cleaning resolved the problem, perhaps closing the hatch yet again played a role, but others in this situation should try cleaning first.