What does serial number mismatch mean?

The serial number mismatch is an error message related to the Signing Service. It usually looks like this:

“Serial Number Mismatch. We strongly advise to go through the Pre-Signing Process in order to retrieve the actual Step-Up Serialnumber”

This error message indicates that something has changed in the user's registered evidence ID and that the user did not perform a re-identification corresponding with the step-up process described in the reference guide of Signing Service.

Often, this error happens, e.g., if:

• Users change their SIM card or mobile phone number
• Users switching from the password & SMS code method to Mobile ID as signature approval means without re-identification and registration for Signing Service.
• Users have forgotten their secure password using their password & SMS code method (PWD/OTP) and have yet to get re-identified.
• Users' ID document (ID card or passport) has expired, and the users have not re-registered again with their new ID-document

You can visit our page. Please check your signature to get exact information about your signing error.