I believe you are wrong, (according to the Unsolicited Goods and Services Act - "unsolicited" means, in relation to goods sent to any person, that they are sent without any prior request made by him or on his behalf.), but as you say the OP now seems to be happy.
That's not what happened though - the OP got what they ordered, entry to the football for a 4 year old. They didn't use the extra service the club sent them in error - you can't therefore compare it to buying something, being given the wrong item and using that item - they didn't.
It's not up...
Not a fair analogy at all!
More akin to buying a jumper from M&S and as well as the jumper they'd put a shirt in the bag which wasn't noticed but was charged for. A refusal to refund for unsolicited goods on the grounds that they may have been used just doesn't stand up.
A season ticket for a...