Problem of Access to Diagrams

I managed to generate documents and create requirements in my project. So, I downloaded the packages required to each one. Thus, I started to change the contain of templates related to the generation of the docs and I created some requirements. In addition to that, I renamed the project using the F2 (As I am working on a French project, I put accents in the name, what was not appreciated in the templates related to M2DOC) . After explaining the recent actions that I performed on my project, I can tell you that I am facing an issue right now. I have no access to anything in my project, I can’t open any diagram whatever is the layer.
Can you give me some suggestions in order to solve this problem?
Thank you in advance.
Best regards,

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