Amazon Ad code

Hi, this is probably a noobiesh question but the fact is, I couldn’t find a solution:
anyway, I’m trying to insert an amazon code into posts through the “HTML” and then I add content (text) from the “Visual” tab what happens is that amazon code is on top and the text is below, I want to align that code to the left and the text right next to it. WP align buttons don’t work, they do work instantly but once I publish/update the post it goes back to the initial position.
I’d appreciate any help.
Thank you!