Problems upgrading to full version of norton 360 on android phones

hi, i have just purchased norton 360 for my galaxy ace and xperia sola. I downloaded norton from play store, went through all the screens, but when it comes to the screen where you can either upgrade to full version by clicking on the link and buying it through google or clicking on 'i have already purchased the full version' , I cannot get the i have already purchased link to work. I deleted the norton and downloaded again but still same thing. The line of writing stays yellow but clicking on it does nothing. I did the same for my hubbys phone thinking it may have been an issue with mine, but same thing happens. Can anyone give me any ideas please?