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: ['l', 'i']
Example Output: i, l

Example Input: ['1367', 'h', '4153', '1587', 'h', 'b', 'n', 'u', 'n']
Example Output: b, h, n, u

Example Input: ['9003', '703', 's', 'd', '8773', '2375', '9169', 'n', 'i', 'o', '4777', 'c', 'f', '2471', '1387', 'r', 'i', '7287', 'i', '2453', '21', 'z', '479', 'b', 'c', '5819', '6949', '4069', 'm', 'b', '4863', 'c', '4063']
Example Output:
b, c, d, f, i, m, n, o, r, s, z