For whatever reason, you have mistakenly ended your draft and now it is showing that it has been completed.
While we don't have a way to undo that, you can get it back by re-creating your draftboard.
The first thing you'll want to do is take a screenshot of your entire draftboard that was ended. This way, you can at least have something to reference. You can also view all previous drafts from the settings in the mobile app.
Step 1 - Make sure your League Type is set to Dynasty. Even if your league isn't a dynasty, temporarily change it to this.
Step 2 - Add a supplemental draft. These only have a maximum of 10 rounds, so it's possible you may need to create additional drafts to get to your desired rounds. You can only do one at a time, though.
Step 3 - Set a draft order. Set this to how it was before you ended your previous draft, not to where you left off.
Step 4 - Re-assign traded picks. Click on the individual tiles to re-assign a pick to another team.
Step 5 (optional) - If players have already been taken in your previous draft, you'll want to put in placeholders in any slots as a way to bypass any picks. This will allow you to start with the team that you left off with.
For example, if you made it to the 4th pick in Round 1, you'll want to give picks 1, 2, and 3 very lowly-ranked players, so that you can start with pick 4.
Once you are ready to begin your draft again, it will skip over those picks and you can start drafting as normal.