First, you can easily upgrade to ESSENTIALS. Just log into our site and proceed to purchasing an ESSENTIALS subscription. Our system will give you an automatic discount based on the subscription time left in your current ADMINTOOLS susbcription.
Regarding the payment, I think you have a problem with your browser's cookies since everyone else is able to pay and you did manage to pay for the ADMINTOOLS subscription. You need to clear your cookies first. The exact way to do that depends on your browser but this page on deleting cookies
seems to cover every possible browser, even some I had not heard of. Then come back to our site, log in and proceed to purchasing an ESSENTIALS subscription. If that still fails please post back, we'll arrange an alternative payment through PayPal.
Nicholas K. Dionysopoulos
Lead Developer and Director
🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
Please keep in mind my timezone and cultural differences when reading my replies. Thank you!