How to update Branch User Field in Sap b1

Hi friends being a very new in SDK developer for SAP B1.

I creted user defined filed in Branch and Department , But I do not know how to update the

created user defined filed through di api c#.

when I am trying to insert some values I am only getting name,description but not my created field.

I will be thankful to all of you if you can help me. please

Thanks in advance.