Missing Customer Number and Name for Sales Order

Hi

I had built a Query on Sales order number , cust no cust name

When I execute the query , cust no and  cust name are missing for some sales order.

Checked in the SQL DB , values exist for all the sales order - Only Issue comes when executing the report

Pl Suggest what might be the problem

Ex

Sales order No  Invoices sales  Cust no  Cust Name

111                          23                1                a

112                           34               2                 b

113                            99

114                             11

Values for sales order 113 and 114 are missing.

Values exist both in SAP DB  and BO DB

Thanks

NK