Hi, I have to re-up this issue as I'm facing the same problem : my settings are correctly set, I have Elementor 3.17.3, Elementor Pro 3.17.1, Mb Settings Page 2.1.11; Meta Box 5.8.2 & Meta Box Elementor Integrator 2.1.10 installed.
When I click on dynamic field I can choose a Meta Box Field, I can go to "Settings" but the select is empty for the fields...
Thank you