It says wait you can’t start the import until the exisitng import is finished.
How long wil it take to finish and
How do i stop it ?
Right now it’s not possible but we plan to add this functionality: How do i stop the database duplication or import process? - #2 by olgatrykush
Imports have a maximum runtime of 30 minutes, after which they are automatically canceled. If this happens, you need to wait and then start a new import.