I dont know....i would call Customer Service @ Six Flags and tell them about it. maybe that Message 87. (15p) is a code Customer Service can use to Look up the problom
My nephews did that too!! Same error message. He tried for a couple of days straight and it still wouldn't work so we finally just went up to the park and they activated it and gave him the free 2 use Fastlane pass. I printed out that error message and took it up to the park that way they could see that he was trying to activate online so that he would get the free Fastlane.