If you want to renew your contract you have to pay the next contract period up-front.
Before the end of each rental period, a new invoice will be generated and you will be notified by an email which reminds you about the renewal.
If you intend to keep the service, that invoice must be paid. If the invoice is not paid on time, your server will be suspended at the end of the billing cycle. The service will be suspended for up to 30 days before it gets terminated (deleted beyond any recovery).
Suspension gives opportunity to the clients to renew an expired game server and still get the same service as before, with all files being intact. 
Our billing system will automatically send reminding emails before and after the suspension. There will be three reminders in total before and after the suspension!

If you don't intend to keep the service, simply disregard these emails.

Keep in mind that we reserve the right to delete the files earlier than within 30 days