Thank you Chris, but I'm not talking about the entry as I'm already staying in Thailand. I'm talking about the 1 month extension at the immigration centre.
Thank you for your reply. But that's actually my question: "I wonder if there are any exceptions and if it really depends on the officers at the immigration." since I'm completely legally in Thailand, got my 2 months tourist visa and could extend like everyone else. So I'm wondering, if and why they could reject me, when there is no limit of 180 days, you know.