Hello! Thank you for playing FFXIV!

Error 601 when trying to make a purchase on the Mogstation can be caused by numerous things. Connection issues, insufficient funds, and multiple attempts with different payment methods. We recommend that you first contact your bank to ensure that nothing on their end is blocking the payment. Then you will need to wait a full 24 hours with no attempts and then try again. If you continue to get the error you can try to use Pay Pal to purchase Crysta and then use the Crysta to purchase your mount.

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