If you are not receiving journey(automation mails), first trace the log.

Steps to trace log :
1. Check generation log [ECMPLOG]
2. Keep tracing until you find the email has hit final delivery server
3. Check log on delivery server [PMTA or Halon].

To Validate the configurations :-

1. If you are receiving mail but the DKIM is not signing on sender domain.
2. Envelope sub-domain is not on sending domain.
Please check if the DNS is done & check if the routing is done. Envelope, Sending Domain and DKIM has to be same domain

If you still find any issue please reach out to DE.