Shoot! I wish I had seen your post before now. The same thing happened to me last week and again today. Out of 4 days trying to fork over money to Disney I was only successful twice!
I was on my phone at 6:45 this morning and tried to but G+ for 25 minutes. The button to buy it was unresponsive. I was able to get an ILL for Rise just fine, but the regular G+ was impossible. Until, at 7:11 when the second drop happened I tried to grab a 9:30 Slinky and the payment went through even though I tried through the regular “Buy G+” link just seconds before. But … I did not know that doing it that way only purchases G+, not the LL. You have to go back to the tip board and get a LL. By the time I realized I didn’t have a LL for Slinky, it was all the way into afternoon. Instead, I grabbed a Smugglers Run for 9:30 which turned out to be for 11:50. The Studios were Messed up today so I knew I would only get 2 rides in with a return time so late.
I talked to a guest relations person under the blue umbrella and she told me about needing to go back out to the tip board after purchasing G+ by selecting a return time. She also advised me to buy G+ at 6:00 am. Right.