Workflow only triggered on manual execution even though it's set to trigger on creation

My workflow on sharepoint doesn't execute when a new item is created in the associated list.

The workflow uses a list item which contains a number and copies that into a reference number field on the new/current item.

I've checked that:

1. workflow is set to run on item creation


2. all logs are written on manual release


3. 
   

   the workflow is executing correctly when ran manually

   
   

   Is there any more troubleshooting I can do to check what's wrong?