You should receive your refund advance funds within 48 hours of the IRS accepting your return.
https://ttlc.intuit.com/community/refunds/help/about-receiving-your-refund-advance/00/27510
It’s been over 48 hours since acceptance and no refund advance
Please reach out to Credit Karma's customer service here for more assistance on the status of your Refund Advance: 1-888-909-8872