Are you asking why the handwritten signature of the first-level cost engineer cannot be uploaded? This is due to technical issues and format requirements.

1. There is a technical fault or limitation in the upload system, which prevents the handwritten signature from being uploaded successfully. This is caused by system updates, network problems or other technical factors.

2. The upload system has specific requirements for the format of handwritten signatures, such as file type, size, resolution, etc. The handwritten signature does not meet the system requirements and cannot be uploaded successfully.