It is the question Master Vishnu is asked most often, and the honest answer is that most difficult periods have entirely ordinary causes. Illness, financial strain, exhaustion and grief can each produce the heaviness people describe, and an ethical practitioner rules those out before suggesting anything spiritual.
What does raise genuine concern is a particular pattern: a sharp reversal across several areas of life at once rather than one at a time; problems that doctors and professionals cannot account for; a home atmosphere that turned heavy from a datable point in time; and progress that collapses at the final stage again and again. Where several of those appear together, the birth chart and traditional diagnostic methods can establish whether an affliction is really present.
Be wary of anyone who tells you at a first meeting that your family is cursed, attaches an urgent deadline, and quotes a large fee — that sequence is the most common form of exploitation in this field. Read about black magic removal, or speak with Master Vishnu for a straight, confidential assessment and a second opinion if you have already been given one.