Debug Database Import Function

I have a client (HTML5) and server side prototype application which includes an import function to read data from XLS file and import the text data into a data base. I have recently tested the use this function for the first time and it appears that it's not work. I am looking for a developer who can trace the code from the HTML import button to the PHP code for import, learn & explain how the import is working and fix the import issue The original developer is not available anymore to fix the issue however my understanding is that this should be trivial and may be fixed easily. One this job is complete, additional back end and front end work is required to make the prototype fully usable.