I guess because it is on a smaller map than the last one I did a bunch of my ships appeared far outside the deployment area.
Some of them even appeared off the screen. Because they are off the screen I can’t select them. Because I can’t select them I can’t delete them.
There needs to be some function that will delete all deployed ships.
On maps I use frequently, I take an empty deployment and save it as “Blank.” This is a workaround but it works for me. I can also copy this blank deployment to other maps as necessary in the deployments folder.