I called the support phone number about this issue. They said there's no way to change it in product. They recommended I print out the return, fix it manually, and the file it by mail. Or they said that the IRS will likely be able to look up my address even if the slash was missing so they said I could e-file if I wanted to but they said if it was concerning to me, then I should file by mail. Hopefully they can fix this issue in the next version of TurboTax Online.
