"Nested" TMs

Question

Good morning! 
 I was wondering what does the "nested" TMs shown in the image mean in SDL Trados 2017. It usually happens when configuring a project from a single file beginning with the option of translating a unique file instead of creating a new project. I normally set up the TMs and the software creates a different TM and disobeys me. How can I fix this? 
 Thank you in advance.

Paul · Answer

Hi Rubén Méndez Suárez , 
 
It means you are using ProjectTMs. These are created when you create your project and they contain a subset of your Main TMs relevant to the translatable text in your project. They can only be created if you used the batch task "Prepare" as opposed to "Prepare without project TM" when you create your projects.

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"Nested" TMs