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: ['i', 's']
Example Output: i, s

Example Input: ['3223', 'h', 'w', 'f', 'y', '1667', '8843', '8759', '9203', '3305', '3549', '5507', '6251', 't', '8319', '9121', '6643', 'u', '4273', '4429', '7543', '7909', '789', '9183', '5729', 'd', '7063', 'b', '6677', 'w', 'x', 'x', 'z', '769', 'p', 'd', 'h']
Example Output: b, d, f, h, p, t, u, w, x, y, z

Example Input: ['y', 'w', 'y', 'b', '4717', 't', '9495', 'b', '7319', '7527', '3513', 'c', '9797', '933', '779', 'c', '793', '1673', 'z', 'n', 'z', '1607', '9487', 'o', 'k', '6185', 'v', 'u', 'y', '5081', 't', 'g', 'q', 'z']
Example Output:
b, c, g, k, n, o, q, t, u, v, w, y, z