Just to clarify, was your tax refund deposited into a bank account that does not belong to you?
If you entered a valid (but incorrect) account number not belonging to you, usually there's nothing to worry about, as many banks won't deposit tax refunds into accounts where names don't match up. You can try calling the IRS to stop the direct deposit if your return hasn't posted to their system yet (and you're willing to get your refund via paper check). For security reasons, the IRS cannot re-route your refund to a different account.
Please click What if I entered the wrong bank account for direct deposit? to learn more.