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: ['2329', 'i']
Example Output: i

Example Input: ['t', 'r', '2959', '2517', 'a', '9959', '729', '511', 'y', 'r', '465', 'c', '687', 'm', 'b', 'm', '3449', '9713', 'g', '8275', '8823', 'a', 'z', 'w', '2185', '6283', '8457', '8137', '7163', '8329']
Example Output: a, b, c, g, m, r, t, w, y, z

Example Input: ['a', 'a', '2647', '5755', 'w', 'e', '7365', 'o', 'v', 'b', 'c', '8661', 'x', '4613', '4545', '4065', '1897', 'l', '1681', '7871', '1265', '965', '3491', 'o', 'u', 'i', '2635', '8583']
Example Output:
a, b, c, e, i, l, o, u, v, w, x