Sometimes flicking the lever a few times isn't enough, gotta leave it overnight.
Get the brake in a spot where gravity can be your friend (might have to angle the bike in the stand if you're internally routed) and then strap the brake lever down overnight. Air bubbles will slowly bubble out in the top syringe.
I've had success doing this by solely lever bleeding on Sram and Shimano brakes (i.e. not using the syringe on the caliper) if you want to skip part of the process. I do not have magura brakes, but based on the youtube video I found it looked like the same process as sram brakes.