DKB giro card limit

Hello community, because I've just experienced it myself and wasn't aware of it before: I wanted to use my giro card (colloquially EC card), not the debit card, to pay for something in the store for around €3,700. The account had sufficient funds and no (transfer) limit was set. The payment was rejected with “not possible”. The second attempt was also unsuccessful and I had to make the payment with a different card (different provider), and that worked without any problems