public Instant getLastLogin() {
        return Instant.ofEpochMilli(Long.parseLong(metadata.getOrDefault("last_login", "0")));
    }
Add attribute.

@param key   the key
@param value the value
@return the duo security user account
support/cas-server-support-duo-core-mfa/src/main/java/org/apereo/cas/adaptors/duo/DuoSecurityUserAccount.java