In this task, you are given an input list A comprising of numbers and alphabets. You need to extract and sort the unique alphabets in the list. The alphabets in the input list will only be in lowercase. Return -1 if there is no alphabet in the input list.

Example Input: ['6597', '7889', 'x', 'v', 'm', 'j', 'j', 'w', 'v', '177', 'x', '8353', '5897']
Example Output: j, m, v, w, x

Example Input: ['2381', '2865', '4821', 'n', 'u', 's', 'p', 'v', 'v', 'n', '1349', '7903', 'm', '193', 't', 'p', 'c', '3521', 'a', 't', '8281', 'i', '151', '4783', 'm', '3387', '9551', 'z', 'q', 'v', '4549', '4411', 'u', '8735', '2645', '359', '2871', '5923', '5071', 'c', '9843', 'i']
Example Output: a, c, i, m, n, p, q, s, t, u, v, z

Example Input: ['3379', 'n', 'b', 'y']
Example Output:
b, n, y