Problem getting postmark to work

My first post is about using postmark for transactional email. Although it is set up correctly I cannot get it to send registration email to my dummy accounts address. I have it set up on the domain at Namecheap and all docs created on Webdock ( from which I use the free version of postmark) but no transactional email seems to get sent. I doubt it is the software (Akkoma) and is most likely me but have no idea where to look. I have not configured Akkoma on the back end, I am using postmark as instructed by Webdock and postmark only. I am not really familiar enough with code to work on this so I thought I would ask here. Thank you for any consideration. My instance is: https://fedimoon.com