MicroBlock
could be a regional problem (call AT&T and ask) or simply you lost internet connection.
I've also been having this problem since the 6th (in South Carolina).
I also noticed that the MicroCell seems to have become very sensitive to the speed of my internet connection. If I'm downloading or uploading a big file on my computer that is taking up my bandwidth (15 Mb down, 3 Mb up), then my microcell will lose its connection (bottom light starts flashing). It's pretty consistent, and I never had this problem until I started noticing other issues on the 6th.