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.

Example Input: ['1985', '729', '169', '1299', 'l', 'z', '6809', '3083', 'w', 'f', '1989', 'z', '889', 'x', 'r', '1601']
Example Output: f, l, r, w, x, z

Example Input: ['6249', '1235']
Example Output: -1

Example Input: ['u', '1577', '8955', 'n', 'l', '8559', '8487', 't', 'k', '1039', '8365', '3087', 'y', 'f', 'e', 'e', 'u', 'r', '7703', 't', 'd', 'r', 'b', 'k', 'o', '9421', '3493', '6187', '361', 'e', 'l', '4839', '3677', 'i', '681', '9987', '5091', 'f', '9689']
Example Output:
b, d, e, f, i, k, l, n, o, r, t, u, y