Start at the basics.
Easy one first - you may have a bad thermistor reading, so the nozzle temp isn’t actually as hot as it should be. Rub some filament on the nozzle when it says it’s up to temperature and confirm that it melts easily. If not, replace the thermistor.
If the hot end is hot, and the filament is moving in the right direction, filament will come out if there is no clog.
If the gear is turning, and the filament stops moving (filament stripping), there’s something jamming the filament in the nozzle, heatbreak, or feed tube. Did you go back to PLA after ABS? Leftover ABS that doesn’t melt completely at PLA temperatures is probably the problem. Take the temp to ABS temp and push it out with PLA. Once purged, drop the temp back down. If you’re still running ABS at ABS temps, my guess would be that the filament broke off in the filament guide inside the extruder, above the melt zone, so the filament is deflecting to the side instead of pushing the jammed filament out.
If there is filament jammed in the filament guide inside, you can sometimes clear it by taking the temp up a bit higher (about 10-20c above normal temp for the filament), loosening the tension on the idler completely, and using a 1.5mm hex driver to try and push the jammed filament through to the nozzle.
Once done, try pushing filament through while it’s still hot manually with the idler still loose and held back. If you can push it through by hand easily, it’s not jammed, and you can tension it back up and give normal printing a try.
So if all this is good, and you’re still not getting filament when you print, it could be incompatible firmware with the slicer version. The firmware can do a retraction in addition to any retraction the slicer is doing, and if those retractions add up such that the filament is above the gears, there’s nothing to pull. They could also retract enough that the filament just isn’t reaching the nozzle when expected in the print, but eventually would have started if you had waited.
For the Mini 1, on a mac, you should be running Cura LE 3.6.37 (or 3.6.40 if you feel experimental) LulzBot | Cura-mac and firmware should be manually selected to use Marlin_Mini_SingleExtruderAeroV2_2.0.0.144_aded3b617.hex (if you don’t have and LCD) or Marlin_MiniLCD_SingleExtruderAeroV2_2.0.0.144_aded3b617.hex (if you do have an LCD) since it will probably try and default to a 1.1.9xxxx version of Marlin.