Assets not showing up after renaming them

Hello! i have a problem. I purchased the Multi Objects Renaming Tool to reduce characters from the names of my files and after that some files dont show up in the viewport but you can still see them in the world outliner on the Right Upper side, as in my picture. What can i do?!


as you can see, the group of objects are selected, and you can see the axis on the viewport and the objects selected on the World Outliner, but they are still invisible or something

im also getting another error on some other objects. They have an error trying to load some bitmaps for the materials

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