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: ['4213', '3595', '7937', 'y', '5723', 'v', 'b', '7007']
Example Output: b, v, y

Example Input: ['9025', '3259', '4863', 'u', '6443', '9931', '627', 'x']
Example Output: u, x

Example Input: ['p', '399', '6687', 'f', '8423', '9243', 'o', 'q']
Example Output:
f, o, p, q