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.

Input: Consider Input: ['6249', '1235']

Output: -1


Input: Consider Input: ['p', 'f', 'h', '1977', '6221', 'i', 'a', 'l', '5225', '8059', 'c', 'w']

Output: a, c, f, h, i, l, p, w


Input: Consider Input: ['m', 'z', '4135', '3867', '2447', '6441', '3001', 'm', 'e', '471', 'l', 'r', '3395', '7397', 'j', 'd', 'i', 'o', 'n', '781', 's', '6605', '4669']


Output: d, e, i, j, l, m, n, o, r, s, z