Customer code changed

I have a specifed cutomer code which is as below

The system changed it to 00469.

os

And it seems some customer codes are changed by system

How to fix this issue/

The customer code would not change on its own.

Have you reviewed History to see when it was changed?

See Audit transaction history | Manager

We do confirmed the customer code system has some bugs now.

We created a new one 00778 as below on yesterday. But it disappeared on today.

@Lubos, I can confirm that Customer code does not appear on Sales Invoices and Receipts. I did not check others.

have you looked into the customer was created but had not been blank for quotation,order and invoice? We found some cusotmer will be disappear