My friend is banned, trying to figure out why

[a_tasty_serving_of]

I have a friend by the name of rtdmark and he's listed as banned here. I can't quite figure out why. He wants to buy some buds off of me and I've known him for a long time and he seemed reputable but I wanted to know if theres some issue with him. I searched through steamrep and here in the forums and can't quite figure it out. I also wanted him to add to my rep thread as we have done many transactions in the distant past. He is rarely on so I havne't got around to asking him directly. Anyways, a response would be appreciated. THanks.

[Butane]

he should add petey or me to discuss it, we don't have a public list of members and why they are banned for all to see.