You can have multiple DKIM DNS records on the same domain. It is a recommended and safe practice. Check out how to add multiple records with an example.

If you’re coming across the message “No DKIM keys saved for this domain” for a new domain you’re trying to add on Microsoft office 365, resolve it now. Here is how you enable office 365 DKIM keys.

Stay under the SPF void lookup limit of 2. Tricks that you can deploy at your organization to never exceed the maximum limit for SPF void lookups for your emails.