Destroyer unavailable to produce after using warbonds to speed up research

On day 1, I used warbonds to finish the research for level 1 destroyer.

When I went to my city (with a naval base) to produce a destroyer, the option was greyed out.

The small window near my mouse said "currently producing" (this was not the case)

I have more than enough resources to produce a destroyer.

Why is this happening?