I applied for the refund advance & I was wondering when I could be able to use my virtual card for online payments. My availabile amount still says 0.00

You should receive your advance within 48 hours of acceptance of your tax return, on the temporary card from the time your return was accepted.  

Please make sure you check your junk/spam folder. The sender will be turboprepaidcard@email.turboprepaidcard.intuit.com. 

Please refer to the following help article for more information.    

About the Refund Advance temporary card - Community    

Update: I applied for the refund advance and it said that I would receive my refund within 1 hour. I received it in about 6 hours. I got an email confirmation about my available funds on my temporary card.