I'm running a file-drop triggered automation to import people from a CSV list into a MobileConnect Contact List. I've created the Import Definition - very simple, just 3 fields (contact key, mobile no and locale). I've tested the import definition and mapped the fields and it works fine.
I've just built an Automation in Automation Studio for it, with only this one step (Import Mobile Contacts). It is triggered by a File Drop on our FTP, and a file naming pattern of begins with 'SMS_'. However when I run the automation, it fails every time.
I get the error
'File SMS_Master2.csv not found'
I don't understand - how is it not finding the file? The trigger of it arriving is what started the automation.