Leaking lever - Shimano brakes M365
The first thing to check is that the rubber gasket in the brake lever reservoir is fully intact and in place. They can get both torn and clamped out of position, and that would be consistent with having just been opened up for bleeding. Make sure the reservoir is turned horizontal when open so fluid can't spill out.

If it's leaking anywhere else, there's not much that can be done other than replace the lever.