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

Example Input: ['8281', '4831', '1329', 'g', 'e', '8879', 'n', 's', 'x', 'j', '6305', 'j', '921', '3677', '5107', 'n', 'j', '9285', 'a', '5329', '6671', 'c', '9283', 'l', 'a', '7907', 'q', '7605', '855', '6477']
Example Output: a, c, e, g, j, l, n, q, s, x

Example Input: ['7503', '3389', 'r', '5731', 'f', 'b', '5153', 'o', 'z', 'i', 'r', 'm']
Example Output:
b, f, i, m, o, r, z