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]: ['8975', '7199']
[EX A]: -1

[EX Q]: ['g', '4165', 'n', 'w', 'n', 'e']
[EX A]: e, g, n, w

[EX Q]: ['j', 'j', '5277', 'v', 'h', '7643', '1341', 'm', '2197', 'r', 't', 'u', 'o', 'e', 'l', '5453', '1051', 'p', 'z', 'r', '1361', 'n', 'v', 'v', 'y', 'h', 'b', '6775', 'i', '2281', '3671', '8035', '159', 'r', '6985', '1797']
[EX A]:
b, e, h, i, j, l, m, n, o, p, r, t, u, v, y, z