Why Table of Content page is generating multiple time when i executes the form each time ?

[Vijaya Naik]

I have written the TOC code and some other functions in while loop. When i execute the forms each time , the output will get generate and it will be in pdf format. And each time one TOC page also gets generate. How can i have only one TOC page and it should get update when forms are executed(TOC contains form names and page number). TOC is table of content in tcpdf.