ESA new look not accessible

[KRC_ICT]

I am not able to access the new email web UI with the error message:

Either API server is not started or is unreachable. 

[Ken Stieers]

Go to Network/Interfaces and make sure you have enabled the api http/https.

You might also have to go cli and enable trailblazer.
(article is for SMA, but its the same on ESA)

https://www.cisco.com/c/en/us/support/docs/security/content-security-management-appliance/214391-administrative-details-on-trailblazer.html