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: ['a', 'p', 'y', 'l', 'l']
Example Output: a, l, p, y

Example Input: ['k', 'n']
Example Output: k, n

Example Input: ['9285', '3907', '7987', '6897', '6789', '225', 'w', '5699', 'c', '515', 'g', 'z', 'd', '119', 'g']
Example Output:
c, d, g, w, z