I have recently purchased itunes match, and when I enter my account password, and click "add computer" to activate itunes match, nothing happens.

I have a 2011 13-inch Macbook Pro. I had iTunes match last year, but when the subscription ran out, I did not renew until about a week ago. When I initially purchased the subscription last week, iTunes said that it couldnt match my songs at that moment because of an issue. Today, whenever I enter my account password and click "add computer", nothing happens. I have tried quitting and restarting iTunes. Please help!