This is truly frustrating. I emailed support with the same thing the other day before it reached the 1500 and I was told, oh you just have to wait until you get to 1500. Well I did and now three items show that they can be collected yet it's not letting me get them.
Yes, I'm having the same problem. It was ready for me to collect when a message about server maintenance was going to be done for 10 minutes. I left and came back only to find, it shows I can collect my XP Barrel but it's not letting me collect it.