Hi, @rsmiller, thanks for reaching out to us with your question, and welcome to the Seller Community!
With Square, you can accept any US-issued and most non-US issued credit, debit, prepaid, or gift cards with a Visa, MasterCard, American Express, Discover, UnionPay or JCB logo. It sounds like your customer may be attempting to use a card we do not support for payment processing.
You can view more information here on accepted cards.
Regarding this payment, were you attempting to process the transaction manually by chance?
If so, Square requires all of the following information for transactions entered manually:
1. Complete card number
2. Expiration date
3. Security code/CVV
4. Billing ZIP code
If you are unable to swipe the debit card, then your customer will need to pay with an eligible card, such as a chip card instead.
Let us know how you go here!
Community Moderator, Australia, Square
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