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: ['6627', '8037', 'q', 'e', 'j', 'p', '9613', '9317', 'm', 'm', '5345', 'f', '8105', '5665', '4175', '4793', '3707', 'i', 'b', '6745', '747', '8329', '1481', 'b', '8949', 'n', '4803', '1359', '3533', 'f', '543', '3003', '6943']
Example Output: b, e, f, i, j, m, n, p, q

Example Input: ['477', '3931', 'g', '5967', 'm', '9845', '1607', 'a', '1749', 'k', 'j', '7945', '9125', 'v', 'n', 's', '5185', '1117', '17', 'x', '4149']
Example Output: a, g, j, k, m, n, s, v, x

Example Input: ['6769', '1057', '1021', 'n', '8231', '9173', '8123', 'a', '6053', 'q', 'y', '883', 'r', '1215', 'x', 'o', '9531']
Example Output:
a, n, o, q, r, x, y