PMPro Infusionsoft "No Tags Found"

Dear strangerstudios, I am experiencing some errors in infusionsoft + pmpro. I already put the username / id ( which is the xxx of the xxx.infusionsoft.com) and the api key but after saving the settings it doesn’t show the list of tags (from my infusionsoft account). I always have the “no tags found” notification. Is there something wrong with my infusionsoft setup? Hoping for your kind and positive response. Thanks.

http://wordpress.org/plugins/paid-memberships-pro/