Thanks, I have now found out from my mrs what happened, she ordered 3 tickets online and they all came up as adult tickets, she changed one to u-16 for my youngest son, kept mine as adult and kept my 16 year olds as adult.
She thought as he is 16 and not U-16 that's what she had to order.
If you want a job doing, do it your self FFS.
Thanks to all that have replied about the Millwall tickets.