Adjustment of the binary trees comparison function

Analyze the provided code of the is_equal function. Identify and correct the logical flaws that lead to incorrect determination of the identity of two binary trees TreeNode. After correction, the function should return True only if both structures completely match in node placement and their values; otherwise, it should return False.

class TreeNode:
    def __init__(self, x):
        self.val = x
        self.left = None
        self.right = None

def is_equal(obj_1: TreeNode, obj_2: TreeNode) -> bool:
    if obj_1 is None and obj_2 is None:
        return True
    if obj_1 is None or obj_2 is None:
        return False
    if obj_1.val != obj_2.val:
        return False
    left = is_equal(obj_1.left, obj_2.left)
    right = is_equal(obj_1.right, obj_2.right)
    return left and right