You are never too late for orthodontic treatment. And 24 is definitely not beyond correction. The only factor is that the growth has completed in your case and the bone remodelling takes some time. The only factor would be the treatment duration. In younger patients, the bone remodelling takes place early at a lesser pressure and also the bone deposition is faster and hence lesser time. But as we matures, the bone deposition takes a little longer. Same case as a younger bone fracture heals faster. So go ahead. Get that corrected smile. and be happy.
There is no age bar for orthodontic treatment infact your age is perfect for the treatment. Dentist has to consider some points into his mind while starting the treatment. some investigations like model analysis and radiographs are required before starting the treatment.
I suggest you to visit your dentist and get braces on.
wish u a healthy smile!