Hi Raina,
Did you check the available notes?
SAP Note 302497 - Additional cust. fields not displayed in 'Additional data B'
SAP Note 209278 - Display of customer-specific fields in sales docSAP
SAP Note 386694 - Additional data not displayed in screen 8459 and 8309
SAP Note 420546 - Additional data B and transaction variants in sales order
Extrema ratio, check the VBFS transaction