Hi Cliff,
Thank you so much for the additional advice and my apologies for the lack of reply during the holidays.
As per your last message, I removed and re-added the connectors and changed all references throughout the flow from 'Column 1' to 'Title'. Unfortunately, the exact same error appeared.
There must be something specific about my data that is preventing this method (and the previous methods that you have suggested) from working. I am hoping that someone from within my organisation might be able to find a method that works on my data. If so, I will be sure to post it here!
Thank you so much for your ongoing advice and troubleshooting Cliff, I am very grateful for all of the effort you have put into this.
I will mark this thread as solved, as the first method that you proposed on 22 March did work (just not on the List that I need it to!).
Kind regards,
Nic