I'm sorry to hear that your Christmas tree is leaning. This could be due to a number of reasons, such as a loose branch or a base that is not secure enough. I recommend checking to make sure all the branches are properly attached, and also looking at the base to see if it needs additional support. Additionally, if the tree is still leaning after making sure all the branches are secure and the base is stable, it might be due to an imbalance in the weight distribution of the ornaments and lights. You can try rearranging the decorations to see if that helps.