I am in the same situation. If you haven't filed your 2019 taxes yet and are expecting a refund, then just file with the updated info; if not, then the IRS will use the info from your 2018 taxes. The problem is that, while I got a refund for 2018, this year I owe so TurboTax didn't ask to update my direct deposit info. I have switched banks since 2018 so the IRS is going to send to a closed account. There's not much we can do but wait for the following:
1. Wait until the bank rejects the direct deposit. The IRS will then mail the check instead.
2. Wait until the IRS finishes building a promised web site where you can update your information.
Check here for updated news: https://www.irs.gov/newsroom/economic-impact-payments-what-you-need-to-know
Since direct deposits are planned to start on April 17th, the web site will likely not be ready in time.