Yes flashing green/red lights indicate that the Operating software on SD Card has become corrupt and or there is a hardware fault with the SD Card.
Your BEST way forward is to get a new card (from a shop not the internet because of fakes) and flash the card with the B2 software as per instructions on the Brennan Web site.
Or just order a new card from the Brennan web shop (comes with software pre loaded).
Also when you install the new card the first thing you should do is a web upgrade to ensure the LATEST version of the OS is installed.
Fred