Billing Number and XBLNR Number is not Generated Same. Even after maintaing 'E' in VTFL

Hello People,

I person Maintain 'E' successful VTFL successful for Refernece Field successful SAP.

But Biliing Number and Reference Number is not Generated Same.

Recent Development: I precocious updated NR Status of the Number from 2411100015 to 2411100001.

Recent Billing Number: 2411102305 but the Reference Number: 2411102319

Why the discrepancy? Both Number Should Match?