Strange behavior of REST API in connection with Relations

System Information
  • Strapi Version: v4.14
  • Operating System: Ubuntu Linux 18
  • Database: MariaDB / MySQL
  • Node Version: 18.17

Hello all,

I defined some Collection Types. One of them contains some of these of collections as a relation. The strange thing is, some of these relations I can create and update over REST, some of them not. All Of the collection types are accessable, that is not the point. But I can not find the reason, why some of relationships are not createable or updateable.

Exists there a hint?

Thank you very much,
Sven