Redmine

Hello Redmine Community,

I am encountering an intermittent issue with file uploads to our Redmine server via an API and am seeking guidance or solutions from the community.

Issue Description:
I have a test script that simultaneously uploads multiple files (sizes ranging from 10kb to 300kb, types including txt, pdf, and png) to our Redmine server. The files are consistently the same in every upload attempt. Sometimes, all files upload successfully, but occasionally, one or two files are rejected by Redmine and fail to upload.

Observations:
・The issue is intermittent.
・The failed uploads return a 422 Unprocessable Entity error.
・The same files sometimes upload successfully, other times not.
・The application log shows a failed PUT request to Redmine, and the Redmine log indicates a 422 error but doesn’t provide detailed error messages.

I have included below snippets from Redmine logs during a failed upload attempt.
I would greatly appreciate any insights, suggestions, or similar experiences that could help in resolving this issue.

Thank you in advance for your assistance!