Wi-Fi connection at Starbucks

I have a new MacBook Air and for the past couple of months I have bee going to Starbucks and using their Wi-Fi with no issues. The is the third time now I have have logged on and it says it is connected but the Starbucks screen does not pop up and I can use safari or chrome. I have tried renewing the DHCP lease. I have started it and restarted it with no luck. Any suggestions??