CleverReach is DMARC capable via SPF and DKIM.
To configure DKIM, see this article: https://www.cleverreach.com/en-de/newsletter-tool/sending-newsletters/dkim/
Add 'include:spf.crsend.com' to your SPF record. For more information, please visit: https://www.cleverreach.com/de-de/newsletter-tool/newsletter-versenden/spf-test/