Amazons are much like Humans, they are all different and then again, much the same. And that includes sleep cycles.
In your Amazon's natural range, they wake to the Sun, communication with their family group, commonly with volume and set-off on the morning trip to search for food. Mid to late morning, they gather again and group nap. Early afternoon it back out for another search and then back for an afternoon nap. yet, again another search and then an evening social gathering with Volume followed by the close of day as the Sun slips quietly into night.
Any day may have more searches or less, or longer naps, or higher levels of vocal interactions. Add mating season, nesting and raising this years batch, and around the calendar year we go.
As a Companion Parrot, your Amazon's life is much smaller and less active. Sleep can fill a larger part of a day or period of a day.
This is why, it is so important that 'we' provide toys they can expend energy upon. Provide toys that hide food within to extend that type of activity and provide means for they to excise their Wings, even if it is just flapping while standing on our hand as we move around the home.
I hope that his helps!
FYI: Please take the time to read the two Threads at the top of the Amazon Forum, which are highlighted in light blue!