Submission service on data server not found. (404) Urgent

Hello! I have a tool that is giving the Submission service on data server not found. (404) error when I try to submit a new survey.
The tool itself is fine, with 0 errors showing on the ODK validation form, and the survey elements work fine. The issue is trying to save.

Thank you!

Welcome to the community, @opt! Could you kindly share with us a screenshot of your issue so that we could understand it pictorially?