When you sign up for Flux, we ask you to provide consent for your bank to share your transaction information with us. This includes information like your account number, the details of the retailer you shopped at, and the last four digits of the card you used to pay. Our privacy policies go into detail about exactly what information is shared with us by each of our banking partners.
We need this information in order to be able to generate your digital receipts - without the information sent by your bank, we won't be able to identify your particular transactions in the list sent to us by our retail partners. It's only if we are receiving both sides of the transaction (from the retailer and from the bank) that we're able to identify a single transaction and create a digital receipt.