LazarusMidnight

I am trying to but L$ so i add $30.74 to it though it gives me the estimate of 31.40 usd. so, I dropped the number to $30.00 the transition fee is .40 so why can I not buy L$? I keep getting this error "An attempt to purchase Linden Dollars for your account via the LindeX page on secondlife.com has failed." can someone hekp me with this issue. im using the regular instant buy, as i have always used & have never had this prob.