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: ['3147', '9807', '5313', '6311', '737', '1555', '5803', '3437', '5665', '3973', 'o', 'f', '7871', '1721', '7833', '2933', 'b', 'b', 'n', 'm', 'k']
Example Output: b, f, k, m, n, o

Example Input: ['9555', '5983', '1853', 'c', 'z', 't', 'p', '9041', 'd', '5919', '1621', '345', 's', '2647', '4261', '8611', 'w', 'x', 'p', '9103', '2599', '5101', '9261', 'k', '7437']
Example Output: c, d, k, p, s, t, w, x, z

Example Input: ['i', '6915', 'p', 'o', '2911', '9241', 'g', '1177', '7817', '1889', '1717', '1679', '1985', 'b', 'a', '2969', '8939', '7581', 'l', '6499', '627', 'z', 'g', '3043', '7961', 'b', 'y', '7293', '4165', '5965', '7955', '6695', 'p', '2195', 'l', 'e']
Example Output:
a, b, e, g, i, l, o, p, y, z