What is the plugin? Please provide a free download link.
this does not appear even if I translate some words. Because the source text is incorrect.
Do you mean the English string in the plugin source code is not exactly the same as the source string in the PO file you translated? Or are you just pointing out that the source file is missing?
Please be clear how you’ve verified this as the reason for text not appearing.
Failed to find source file matching “src/admin/components/Reports.vue”
This file is probably not shipped with the plugin. The author will have extracted strings from this file in a development environment and hopefully shipped a generated srings template instead. The source code does not need to be present in the plugin if they’ve provided a valid template.
Loco Translate cannot extract strings from .vue files anyway. Also this tells me the translation is probably loaded into JavaScript, which may be relevant. We can get into that once you’ve provided some clarification on the above.
How can I rearrange the source text? Am I authorized to do this?
I don’t understand what you’re hoping to do, but the answer is probably that you shouldn’t rearrange anything that was prepared by the plugin author. You should sync source strings to their provided template. If it doesn’t work, there may be a different reason.