Gravity is not the only force. There are other forces, too. Multiple forces can simultaneously affect a single object. Forces can counteract gravity, making an object move against the direction of gravity. Such facts do not disprove gravity.
Flat-Earthers take the fact there are objects that move against the direction of gravity as ‘evidence’ of the non-existence of gravity. They are wrong. There are forces other than gravity affecting the object, having the opposite direction from gravity, with at least the same magnitude.
Airplanes and birds fly because of lift and thrust that is greater than the force of gravity. An object can be stationary atop another object because of the normal force. Hot air balloons, clouds, and eggs in salt water can float if their buoyancy exceeds the force of gravity affecting them. Pieces of paper can go upward and stick to a comb because the electrostatic force attracting them is greater than gravity. An indoor skydiver can float because of drag from the wind is the same as the force of gravity. Fridge magnets can stick to the surface of a fridge because of their friction is holding them against gravity. A floating globe floats because of magnetic force repel it up against gravity. A wrecking ball does not fall down because of the tension from its chain holding it against the force of gravity.
The force of gravity can even counteract each other in the form of counterweight. An elevator (lift) that takes us up and down in a skyscraper has a counterweight having about the same mass as the elevator itself. This way, the motor does not need to hold the entire weight of the elevator and spends much less energy.
All the phenomenon where an object is in motion against the direction of gravity can be explained by mechanics and physics in a consistent manner.