The inability of doctors to diagnose illness does not immediately prove that it is black magic (which is an overused and abused term). Fear that one is a victim of black magic seems to cause more harm than black magic itself (and there are not many capable of real dark arts today!) I have personally seen folks who stop seeking medical help with the assumption that they are victims of some kind of magic or entity attack, which can be disastrous.
If you still believe it is black magic (FWIW, a remote sweep of your energy does not indicate any attack by malicious entities or interdimensional parasites):
- You can play Angelic Intercession audio and the Exorcism audio (as you have already tried the curse removal one).
- If you have created a servitor, you can also request it to shield you and reenforce the shield every few hours.
- Lastly, listen to the album, Alchemy of Love - in a loop. A lot of times, sabotage occurs within, while we spend ages looking for an external cause - the higher Love vibration will wash all the negativities away.