Q: What should I do if my submission is still awaiting an editor assignment and the journal editor hasn't replied to my mail?

If you visit the home page of Applied Intelligence (a Springer journal) here, and scroll/swipe to where the journal metrics are provided, you will see a metric for the number of days from ‘Submission to first decision’ too. This says 18 days, which is usually working days and not weekdays. So, technically, it has been 15 days. Of course, they may be facing some challenges assigning an editor, but that could be an internal matter. So, you will need to wait for some more days, say, the end of this week, to see a status change.

As you’ve already written to the editor once, you needn’t write to them again for, say, two weeks. If of course things haven’t changed until then, you could write again asking about the status. If needed, you could mention the metric provided on the site. Additionally, you could say that you are quite eager to know the status and/or outcome of your manuscript, as it no doubt has an academic/professional impact.

In the rare case that they don’t reply to your mails, you may consider withdrawing and submitting your manuscript elsewhere. If so, do keep in mind all the necessary points for withdrawing and submitting elsewhere, as provided in this resource: Should I withdraw my paper if the journal is taking unusually long to process?

Apart from that, you may also find the following resources helpful:

• What is meant by "Editor assignment pending" for a Springer journal?
• The status of my paper is "Editor assignment pending" for more than two months. What should I do?
• Keep calm and wait: A guide to understanding journal statuses [Handbook]

All the best for whatever comes next!