A lot of times when this happens, it is because you have set up a tiered pricing method for your account, but you haven't added names or descriptions for your tiers! 

To solve this: Click on "options" on the left hand navigation menu, and then expand "Pricing."  You can either add names & descriptions to all tiers, or you can change to 1/3/6 month static pricing which does not require names or descriptions since it is a simple monthly price.

If that doesn't solve your inquiry, please reach out to us with some detailed troubleshooting information.