The problem is you...you are scaring it...poor bird.
If it was an aviary bird sharing with another Amazon or as part of a group, it's no wonder it objects to such close human company. It is not a good idea to buy an aviary bird at that age and expect it to turn into a companion bird overnight. You have a lot and I mean a lot of trust building to do. You need to read carefully the pinned topics in the training section on reinforcement.
You must stop trying to approach the bird and scaring it like that. You must only approach very slowly to the point where the bird starts to show discomfort, then you must retreat. It will take a long time for the bird to get used to the new surroundings, if it ever does. Make sure that the cage is against a wall on one side, and partially cover part of the cage with a cloth, so that the poor bird has somewhere to retreat to where it feels it isn't being threatened.
You have to be kind to this bird and give it time and patience and not cause it stress. If it is one year old, you will also have the additional challenge of hormones coming to the fore as it approaches two. Is it male of female?