pdf files open very slowly and after a certain page, the pages are blank

You have posted this any number of times aleady. I have personally given you a very deep technical analysis of what the problem is based on the sample files you provided. The original content from InDesign of these PDF files is exceptionally and unnecessarily complex. I have both in private email to you and via these communities told you exactly what you need to do to fix the problem. I even did one such file for you and sent it to you via e-mail.

There isn't a problem with the software, but rather your content.

And no, Adobe does not provide a free service to fix your files. We did provide information as to how you or your designer can fix them.

Please do not repost this issue again.