[Solved] Error code -10

[Harumph]

I am new to OO Base and have created my first DB.
I get this error code when I try to enter a new record:

SQL Status: 23000
Error code: -10

Attempt to insert null into a non-nullable column: column: SupplierName table: Suppliers in statement [INSERT INTO "Suppliers" ( "Category","Sub-Category") VALUES ( ?,?)]

I am guessing it has something to do with the Primary Key, but can't figure out where I screwed up.

ANy help out there ?
Thanks

[FJCC]

How are you entering the data, from a form or directly into the table? What have you set to be the primary key? Can you up load the odb file? There is an Upload Attachment tab just below the box where you type a response.