I too recently had a brake bleeding issue, never had one before. The pads were pushed out against the disc but could get no resistance at the lever.
I tried everything including taking off the lever and holding it up in the air to ensure it was highest point in the system.
In the end I pushed the pistons back into the callipers, which forced brake fluid back up the hoses. That brought out what I can only describe as pepsi brake fluid, it was so aerated! You might try that or using a syringe to force brake fluid up from the bleed nipple. It worked for me.
