Command.ExecuteNonQuery() Error Occurring NULL Value

Here is the table that I am wanting to insert the information into (BTW I am wanting the UserID, EntryDate, Note) On my page i do have a text box for the UserID as well as a Note textbox. When I hite the submit button on my page I am already sending the UserID textbox information to be sent to another table (called RequestTable). However, I am wanting to take that same UserID and insert it into the RequestNote table as well. Let me know if you have any questions for me to further explain anything.

**RequestNote**
RequestNoteKey (PK)  (has identity set to yes)
RequestKey (allows nulls)
Note
EntryDate
EntryUserID  (allows Nulls)****This is my stored procedure that I am calling called "NoteInsert"***
@Note nvarchar(1000),
@EntryUserID nvarchar(50)
AS
 
INSERT INTO RequestNote (
Note,
EntryDate,
EntryUserID)

VALUES (@Note,
GetDate(),
@EntryUserID)

RETURN
GO

****THIS IS THE PAGE THAT CONNECTS THE USER INTERFACE AND STORED PROCEDURE***
public static void AddRequestNote(string requestNote, string userID)
{
using (SqlConnection connection = new SqlConnection(connRequestNote))
{
using (SqlCommand command = new SqlCommand("NoteInsert", connection))
{
command.CommandType = CommandType.StoredProcedure;
command.Parameters.Add(new SqlParameter("@Note", requestNote));
command.Parameters.Add(new SqlParameter("@EntryUserID", userID));
connection.Open();
command.ExecuteNonQuery(); <--THIS IS WHERE I GET AN ERROR THAT SAYS Cannot insert the value NULL into column 'RequestNoteKey', table 'RequestNote'; column does not allow nulls. INSERT fails
}