Hmm—I suspect the first repeat is a mistake …
Here with slightly different chord values from Jobim's own arrangement in the "Jobim Cancioneiro" book
NB I expanded the first two measures just so you can see the C7b9sus, but it's still 4/4! Melody starts at measure 3

Desafinado (intro from Jobim Cancioneiro) - Antônio Carlos Jobim