The normal way to automatically unlock a previous return is to pay for the 2018 product in that same account. The minimum is usually Free Edition upgraded to PLUS at 19.99. We can tell you how if you go that route. You only have to start the 2018 return and pay immediately. You obviously don't have to prepare another 2018 return since you already filed one.
Or you can speak to Customer Support, and tell them what happened. I'm not sure what they will say. If you're lucky, they may just unlock the return for you.
When you go through the contact process below, be sure you do it from the paid account, i.e., the husband's account.
Hours are 5AM-5PM Pacific (8AM-8PM Eastern) Monday-Friday.
https://support.turbotax.intuit.com/contact
Also see my next comment below.
