Company Number not coming in when using Synapse Data Flow

Hi there
When I use the API to bring in the high level company profile data using Synapse copy data, I have no trouble with the Company Number, it comes in fine.
Now I want to ingest the SIC codes using a Synapse, I have to use a Data flow so I can use the Flatten function. to get data that looks a bit like this:

As you can see the Company Number doesn’t come in, but the other items at level, like company name do.
Do you think it could be to do with the data type looking like a date?

Any Synapse gurus who could help?

Thank you