If you have not filed yet or have been rejected and you entered the incorrect banking information for your refund. You can change it using the link below.
https://ttlc.intuit.com/replies/5619072
If it is accepted, however, it is too late to change it. If the account is still incorrect. The bank will reject the refund and send it back to the IRS. Then the IRS will issue a paper check and mail it to the address you put on your tax return.