In the model browser ("tree") you are seeing the Display Name of the file. By default, the Display Name is set to the file name, but this can be changed by any user. If you open the part file, what is the name at the top of the browser? If it is not the file name, then edit it (slow double click), select all and delete, then Enter. This will reset it to match the file name.
Sam B
Inventor Pro 2025.0.1 | Windows 11 Home 23H2