"A folder or file named … already exists in this location"

What you see: creating a folder, or renaming an item, is refused with A folder or file named … already exists in this location.

1. Look at the dialog you were using.

   

2. Change the name in the field and tap Create again.

Why: names must be unique inside a folder, and that applies to files and folders together.

Other ways to fix it - Choose a different name (up to 255 characters). - Open the other folder and create or rename the item there.

An item that is in Trash does not block you from using its name again.