You are not able to edit a Content Fragment Model (CFM) configuration, and you observe in the logs an ERROR message:
06.05.2022 13:55:25.132 *ERROR* 0:0:0:0:0:0:0:1 1651825525074 GET /mnt/overlay/dam/cfm/models/editor/content/editor.html/conf/myproject/settings/dam/cfm/models/mycompanymodels HTTP/1.1 libs.dam.cfm.models.editor.components.formbuilder.formbuilder$jsp The model config resource is a non-existing resource.
This ERROR message is logged when you configured the Content Fragment Model in a subfolder.
For example: /conf/we-retail/settings/dam/cfm/models/sub-config/we-retail-store-info
Moving the CFM configuration directly to the /models folder should solve your issue.