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: ['9947', '3353', '8643', '4621', '4857', 'y', '7075', 'c', '8911']
Example Output: c, y

Example Input: ['7823', '2933', 'k', '4139', '5585', 'f', 'c', 'm', '2035', 'q', 'z', 'l', '1999', 'q', 'p', '7291', '2091', 'v', '423', 'e', 's', '6089', '4763', '6739']
Example Output: c, e, f, k, l, m, p, q, s, v, z

Example Input: ['c', '8871', '7433', '5093', 'k', '7573', 'x', '8915', '6273', 'o', 't', 'g', '4005', 'b', 'f', 'a', '5491', 't', '4083', 'y', '6731', '8087', 'l', '889', '3233', 'w', '411', 'x', 'v', '1911', '2385', '9437', 'b', 'u', 'e', 's', 'h', '2737', 'v', 'u', '4457', 'b', '3415']
Example Output:
a, b, c, e, f, g, h, k, l, o, s, t, u, v, w, x, y