The most common cause of this is when the name or billing information you have entered does not exactly match the information attached to your card in your bank's records. Double-check this information first.
All other declined card issues on our web store at shop.hydrow.com will always require that you contact the card issuer (bank, credit card company, etc.) to sort out why your transaction was declined.
Card transactions on our website are made securely through our vending partner Shopify, and Hydrow Customer Care does not have access to your credit card transaction information or the ability to resolve card-decline issues.