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]: ['m', '7517', '9361', '9567', '8785', 'k', '5699', '3585', 'v', '1913', '1651', 'g', 'p', '2731', 'q', 'h', '467', 'r', '1091', '9801', 'a', '6645']
[EX A]: a, g, h, k, m, p, q, r, v

[EX Q]: ['j', 'r', 'z', 'f', '1485', '2419', 't', 'd', '6023']
[EX A]: d, f, j, r, t, z

[EX Q]: ['6235', 'g', '8869', 'k', '2631', 'j', 'r', 'e', 'z', '1129', '6131', '4061', 'g', 'c', 'z', '4365', '9297', 'b', 'u', 'j', '2601', 'p', '8227', 'i', 'e']
[EX A]:
b, c, e, g, i, j, k, p, r, u, z