You can only connect an Australian 16 digit Visa or Mastercard debit card to Spriggy. (Your debit card will have the word ‘debit’ printed on it.)
If you’ve tried connected any of the following cards, they won’t work: -
Credit cards
Dual-purpose cards e.g. Maestro
Key cards
EFTPOS cards
If you don’t have a debit card, you can use a bank account as your Connected Account. See this guide to update your Connected Account.