Report to academic institutions: Academic institutions usually take measures to prevent and combat academic misconduct, including writing papers on their behalf. You can report this behavior to relevant academic institutions, and they may investigate and take appropriate measures.
Report to relevant government departments: In some countries or regions, government departments will set up special institutions to deal with academic misconduct, including writing papers on their behalf. You can report this behavior to these institutions, and they may investigate and take appropriate measures.
When reporting, try to provide evidence, including relevant documents, records and other evidence. At the same time, make sure that your report is true and objective and does not involve personal attacks or slander.