Separate names with a comma.
I have the same issue here. @IliasZ have you figured this out yet? Thanks!
Found working solution here: https://download.parallels.com/desktop/v12/docs/en_US/Parallels%20Desktop%20User%27s%20Guide/32922.htm
Dear OP, This problem persists for me with Parallels 15. Have you figured out a solution? Thanks!