Fix Excel Upload Error PHP

I run an internal PHP 8 / MySQL 8 application that lets staff upload a standard Excel template. The file reaches the server but immediately throws a validation error and fails the check.

I need the upload routine working again. That means tracing the exact point of failure and correcting the logic so a valid template passes cleanly. If there is a valid mistake or clearance error, please create a friendly error message indicating the problem.

Doc with screenshots explaining tthe issue is included. Also the excel template used.

Deliverables:
• Updated, well-commented PHP code (or configuration tweak) that accepts the template and inserts data into MySQL 8
• Successful test on sample XLSX files I provide

GitLab access and a staging URL are ready so you can work without touching production. If you have tackled Excel import bugs before, you’ll feel right at home here.