وعليكم السلام ورحمة الله،
بارك الله فيك
You've addressed a very important point masha'Allah
It's rather unfortunate that some Muslims can even doubt that things like sihr or black magic exist when it has been clearly mentioned in the Quran and when our own beloved prophet was affected
It's also unfortunate that people always prioritise using contemporary medicine instead of resorting to what's available in the Quran and the Sunnah
It's sad that people resort to doctor's, medicine's and then if all else fails...they resort to seeing a shaikh specialised in dealing with illnesses such as sihr, 'ayn etc