I import the data of invoices from access to sql, but for new customers the data imported with errors in sql. for example: the invoice with noserial 55555555 is made for customer A, when i import this invoice in sql, it registered for customer B. How can i fix permanently this problem?
This is very much dependent on how you are doing the importing and any code that used by the import process to associate customers with invoices. How are you importing? Do you have visibility into any code used by the import process?