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.

[EX Q]: ['3127', '9253', '5667', '9453']
[EX A]: -1

[EX Q]: ['w', '1081', 'n', '2073', 't', '6351', '5591', 'a', '113', 'w', 'q']
[EX A]: a, n, q, t, w

[EX Q]: ['k', 'n']
[EX A]:
k, n