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.

['o', 'd', '6495', '5211', '341', 'v', '385', 'v', 'g', 'v', 'l', '7631', '2675', 't']
d, g, l, o, t, v

['4749', '4607', '625', '6907', 't', 'b', '8479', '6505', 'r']
b, r, t

['1129', 'w', '615', 'b', 'n', 'u', '1421', '1335', '2551', '8659', '2431', '6641', '495', '3945', '807', 'm', 'f', '4979', 'o', '5257', 'z', '939', 'w', '5427', 'm', '169', 'j', '8533', 'h', '2879']

b, f, h, j, m, n, o, u, w, z