I keep getting the error message "It looks like the Reservation 1 Flow element does not have the correct setting for the one filter."

I  have followed the instructions to the letter, copied and pasted where required, so it wouldn't be down to typos or empty spaces. I see this has been raised a few times, so I have checked what was recommended on the other posts, but have still not solved this. Does anyone have any other ideas please? Should there have been extra steps in the instructions that were left out? Thank you!