Looking back through cells in a column to find Specific Text(s)

Good evening all,

I have tried to use the same process on a different part of my sheet to identify the originating port, and I must have missed something.

Column F of the attached does change if the origin is in the same row, however I am trying to have it look up the last origin in column A and change all rows relating to that origin in column F, until a new origin is encountered.

I am sure it is just a missing comma or something??

Thanks
Darren