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: ['5957', 'd', 'i', 'b', 'e', '5565', 'c', 'i', '2919']
Example Output: b, c, d, e, i

Example Input: ['1595', '2915', 'o', 't', 'c', 'h', '3969', '5407']
Example Output: c, h, o, t

Example Input: ['3347', '7827', 'u', '1363', '711', '8247', '9187', '2783', '2485', '5759', 'k']
Example Output:
k, u