Hello,
This is the Gravity Co., Ltd. Ragnarok Online: Zero Operations Team.
First, we sincerely apologize for the inconvenience caused by the frequent issues.
The error messages 'Server connection failed' or 'Connection to the server has been lost' have been confirmed, and the issue where access is not possible has recurred. The relevant department is currently investigating the matter.
If other causes or additional details are identified, we will inform you through a notice.
We apologize once again for the inconvenience caused to our customers using Ragnarok Online: Zero, and we will do our best to resolve the issue as quickly as possible.
Thank you.
Gravity Co., Ltd. Ragnarok Online: Zero Operations Team