post
https://delivery.panerabread.com/foundation-api/public/unencoded/auth
                  username=<USER>&password=<PASS>&grantType=password

                 'Origin': 'https://delivery.panerabread.com',
                 'User-Agent': 'Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.99 Safari/537.36',
                 'Content-Type': 'application/x-www-form-urlencoded',
                 'Accept': '*/*',
                 'Referer': 'https://delivery.panerabread.com/myPanera/',
                 'Accept-Encoding': 'gzip, deflate, br',
                 'Accept-Language': 'en-US,en;q=0.9'}

Then get these 2 tokens from response
access_token
customerId

and put these 2 tokens in redirect header

'Cache-Control': 'max-age=0',
                     'X-Locale': 'en-US',
                     'User-Agent': 'Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.99 Safari/537.36',
                     'Accept': 'application/json, text/plain, */*',
                     'X-Business-Unit': 'retail',
                     'X-Customer-Id': customerId,
                     'access_token': access_token,
                     'Referer': 'https://delivery.panerabread.com/account/my_payment_methods',
                     'Accept-Encoding': 'gzip, deflate, br',
                     'Accept-Language': 'en-US,en;q=0.9'}

and capture gift card + it's balance