Some flights not being tracked

Hi,I have being tracking an124 in flightaware and receiving email alerts but have noticed alot of flights not be tracked.Right now there is this flight and I did not reveive any email alert.I was just hoping somebody could tell me whats wrong or is it a known bug? Did not get an alert for this departure but did for its arrival

Did not get alerted (tail = CGNPB) for this … /MHTG/KBRO

VFR perhaps ?