If you want to change the second author into a correspondent, you need to provide some reasons to support this requirement. Here are some possible reasons:

Responsible for communication with periodicals: As a correspondent, he needs to be responsible for communication with periodical editors to ensure the correctness and accuracy of papers. If the second author is more familiar with the content and format of the paper and can communicate with the editor better, then they can become communication authors.

Contribution to the paper: The second author may have made a great contribution to the writing and revision of the paper. If they play an important role in the experimental design, data analysis or conclusion summary of the paper, then they should be given the identity of communication authors to better reflect their contributions.

Avoid confusing the first author and the correspondent author: Sometimes, the identity of the first author and the correspondent author may cause confusion. If the second author's contribution to the paper is equal to that of the first author, and they are more suitable for the role of communication author, then the second author can be promoted to communication author to avoid confusion.

Show the author's contribution better: If the second author contributes a lot to the paper, it may be unfair that their names rank after the first author. Promoting the second author to a correspondent can better display their contributions and enhance their academic reputation.