Custom App Icon Shows "!" Instead of App Logo in Scenario List

I’ve developed a custom app (leonai-priority).
Everything works well, except for the app icon in the scenarios list—it shows a warning sign (!) instead of displaying the intended app logo.

I carefully followed all instructions provided in the official documentation here:
[App logo | Make Developer Hub]

I also contacted the Make support team, but the issue hasn’t been resolved yet.

Expected Behavior:
The scenarios list should correctly display the custom app icon/logo (as it correctly shows inside each scenario).

Current Behavior:
In the scenarios list, a warning sign (!) appears instead of my app’s icon. However, when viewing inside a specific scenario, the icon displays correctly.

Please check the attached screenshots demonstrating the issue clearly:

Has anyone else encountered a similar issue with custom apps?
Any insights, suggestions, or solutions would be greatly appreciated.