At present, many mobile phone themes will have some rogue programs. When you download and install the theme, it will be installed with the rogue program. Rogue programs will automatically send information to some charging operators, and some will send it regularly, and then they will be charged. Give you a website to teach you how to prevent and eliminate rogue software/thread -473298- 1- 1.html.
This website is n70. I don't know what kind of mobile phone you have, but the method is similar to this one. You should find it in your own forum.