It sounds like the Pro Micro code has got trashed and is not running any of its USB code. I do think you may get some mileage with the section How to Revive a "Bricked" Pro Micro on the SparkFun website.
It sounds like the Pro Micro code has got trashed and is not running any of its USB code. I do think you may get some mileage with the section How to Revive a "Bricked" Pro Micro on the SparkFun website.