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.

[Q]: ['z', '3219', '6399', '2357', '7597', '357', 'k', 'k', 'u', 'd', '6115', 'w', '2921', '8809']
[A]: d, k, u, w, z


[Q]: ['p', 'f', 'h', '1977', '6221', 'i', 'a', 'l', '5225', '8059', 'c', 'w']
[A]: a, c, f, h, i, l, p, w


[Q]: ['2413', 'o', '3399', '1659', '9429']
[A]:
o