On my second SD card for my V2 doorbell. I formatted both cards when I first inserted them and after a few weeks it is now saying that it needs to be formatted again. This has happened now on 2 different SD cards of various sizes and brands. When I try to re-format them it says “unsupported microSD” and “Format failed”. My guess is this… there is an issue when the card fills all up and it needs to write over older video but I can be wrong.