Identifying unique data from multiple columns/rows

Hi

just wondering if anyone knows how to do this?

I have a sheet with multiple columns of data (and about 5000 rows), of suppliers. Many of these supplier names are repeated many times across about 50000 cells of data. I would like to generate a list of all the unique supplier names across all these columns/rows. I have tried using remove duplicates, but that only works for each column, and of course you can still have the same name repeated in multiple columns. I was just
wondering if there was a quick way of selecting a range and returning all the unique names in that range?

Any help most appreciated.

Thanks

plz share a file

Thanks - that worked perfectly.