How are you testing this, it could be a wrong slicer setting as well, wrong nozzle size, extruder acceleration. Try my test file from the import extruder post. If it doesn’t work while trying to print it could be a lot of things. If it passes an extrusion test (100mm manual extrude, make sure it pushed through 100mm) then it is most likely a slicer issue. if it doesn’t pass the extrusion test probably a firmware issue, could be a hardware issue.
Sorry too much DayQuil, try a 100mm test(bad equals firmware issue, or hardware), if it’s good try my test file (bad equals slicer setting).
If it can’t do a 100mm manual extrusion what is happening?