A few things could be happening here:
It takes some time (up to 15 minutes) to process.
Recommended action: relax and drink a cup of coffee
Some payments fail, that's just what they do. You will receive a "payment failure" email about this.
Recommended action: adjust the payment details and purchase the plan again
You have access to some premium features but not all. We have several plans and not all plans have all features, see for a detailed list of features
Recommended action: take a look at the list of features and decide if you want to go for a different plan.