My Apple Pay card keep getting declined, what can I do

Each time I attempt to pay in stores with Apple Pay, and I select Apple Pay card in my wallet - hold phone to the terminal and when it prompts me to double click, I do so then I follow the next prompt to hold phone to the terminal and it declines even though I have more than enough money on card to cover the transaction. What can I do? It has happened so often and is so embarrassing that I have a card in hand to make my purchase.