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.

['h', '6865', '4019', '8571', 'y', '5575', '7835', '9537', 'n', '875', 't', 'a', 's', '2769', 'p', '1607', 'n', '4087', '961', '7869', '5085', '2131', '4867', 'j', 'h', 'y', '3105', '6609', 's', 'l', '3399', '5013']
a, h, j, l, n, p, s, t, y

['7367', '9757', '9431', 'h', 'a', 'k', '5833', '6237', 'g', '3585', '8665', 'g', '7517', '1561', 'p', 'p', '1307', '3325', 'q']
a, g, h, k, p, q

['6273', 'l', '1385', '5937', '957', 'z', 'n', 'o', '1247', '2417', 'g', 'a', 't', '8571', 'd', '7695', 'b', 'f', '2371', 'd']

a, b, d, f, g, l, n, o, t, z