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: ['w', '1367', '5389', '9515']
Example Output: w

Example Input: ['2393', 'c', '4413', '5529', '1487', '2499', 'i', 's', 'i', '8575', 'm', 'z', '7179', '6637', '9181', 'z', 'h', '2487', 'i', '3779', '2017', '5217', '5013']
Example Output: c, h, i, m, s, z

Example Input: ['3597', 'o', 'e', '679', '2893', 'k', '8693', '239', 'j', 'e', '5161', '2523', '8815', '3955', 'c', '7475', 'w', '1543', '9029', '7447', 'r']
Example Output:
c, e, j, k, o, r, w