I recently got my 3d printer back after lending it to someone who used it without Astroprint and I was having connectivity issues and it would not allow me to update the software, so I re-flashed the most recent software and after waiting for about half an hour, the hotspot is still not showing up. I am using the supported dongle on a RPi 2 model B which I have used with Astroprint for years with no issue. I have erased the card and re-flashed the software three times from two different downloads and have had the same issue
With the new software you would need 2 dongles in order to get a hotspot as the RPi2 doesn’t have internal WiFi. We no longer support dual WiFi network in one dongle.
You can however set it up without a dongle: https://astroprint.zendesk.com/hc/en-us/articles/360000337286-How-do-I-setup-an-AstroBox-Gateway-without-a-dongle-hotspot-