1. First, confirm the specific situation of misnaming the attachment. If the suffix of the attachment is wrong, you can directly correct the wrong suffix to the correct suffix.
2. If the file name of the attachment is wrong, you can try to rename the attachment. According to the content and function of the attachment, try to give it a name that can express its main function or content.
3. If the above methods can't solve the problem, you can try to contact the relevant personnel of Huawei Cup Mathematical Modeling Competition for help. You can communicate with them through the contact information provided in official website or the notice of the contest, explain the problems to them and ask for help.
If the above methods still can't solve the problem, I suggest you contact the organizer of the contest as soon as possible to seek further technical support and solutions. They will be able to provide you with more specific and personalized help.