Outlook automation not working consistently

I have set up a simple automation where the trigger is an email being put into a particular folder on my Outlook email system. This then triggers the creation of a task, taking some of the information from the email.
It runs perfectly when you test it, so I then made it live and put 5 emails into this folder. Only 2 have come across as tasks - I simply can not work out why the others haven’t (I left it overnight, so assuming it isn’t a timing issue).

Any help / pointers on this would be much appreciated.