It
will take a few days even if the IRS states a refund has been sent to your
bank. Typically it is credited within 5 days. You can contact the IRS after the 5 day waiting period has passed on "Where's my refund", if it has been longer than the posted 5 days.
Please
see this from an IRS FAQ:
What is happening when Where’s My Refund? shows my refund’s status as approved?
We’ve
approved your refund. We are preparing to send your refund to your bank or
directly to you in the mail. This status will tell you when we will send the
refund to your bank (if you selected the direct deposit option). Please wait 5
days after we’ve sent the refund to check with your bank about your refund,
since banks vary in how and when they credit funds. (It could take several
weeks before you receive a mailed refund check.)
https://www.irs.gov/refunds/tax-season-refund-frequently-asked-questions