Everything depends on which criteria you use to define human flight:
witnessed, lighter-than-air, heavier-than-air, powered, unassisted, controlled, sustained, survived, soaring, repeated.
The first four of those were met (in chronological order) by the Montgolfier Brothers, Sir Geroge Cayley's gliders, Otto Lillienthal's gliders, Clement Ader and arguably a few others. Any claim not witnessed has to be considered as dubious.
"Unassisted" (no fortuitous bump on take-off run, no gradient, wind or mechanism) seems to be open to debate, requiring careful measurement and reliable, impartial witnesses.
"Controlled" is normally taken to mean "3 Axis Control", yet plenty of known aircraft fly without 3 AC by body movement or 2AC; some military planes only fly thanks to high speed computers. IMO, this means that "Controlled" has questionable relevance as a criterion, certainly since Lillienthal's glides.
"Sustained" and "Soaring" seem to me to be debatable, and also reliant on witnesses, who themselves are not always fully reliable.
"Survived" is obvious!
"Repeated" can be debated if not witnessed.
The debate will never end!