Here are some common steps you can take to try and troubleshoot your email signature issue:

1. Check your browser settings for any plugins or extensions that could be interfering with the signature.
2. Check the email client being used to see if the email signature field has been filled correctly.
3. Make sure that the default email signature exists in the settings for reference.
4. Detect any formatting errors within the email signature that could block it from appearing.
5. Review any third-party apps being used with the email SMTP (Simple Mail Transfer Protocol) that could be causing an issue.
6. Ensure that HTML is enabled, and if necessary, re-enter the HTML code for the email signature.