Hey there,
To go over the basics: to update your SAML SSO Certificate, you will need to update it both in your IdP and in Figma.
 
In Figma, go to Admin > Settings > SAML SSO configuration, and select the "Other" option from the list of IdPs. This will allow you to add the new certificate. Once added, the error message should disappear.

For a detailed walkthrough, please refer to the video below, created by one of our Solutions Architects: How to Update SAML SSO in Figma​​​​​​
 

If you encounter an error about the certificate not matching, it’s usually because the newly generated certificate in your IdP hasn’t been uploaded to Figma.
To resolve this, ensure the new certificate from your IdP is uploaded to your configuration in Figma by going to Admin > Settings > Login and Provisioning > SAML SSO.

If you are still running into issues, we recommend reaching out directly to the support team for further assistance: https://help.figma.com/hc/en-us/requests/new?ticket_form_id=360001744374

Please use your Figma email address and include details about the steps you’ve taken, along with any error messages you’ve received. This will help the team investigate more effectively.Thank you!