amazon web pages not updating upon "sign in" to account.

Starting today, amazon web pages are not updating correctly. The amazon web page appears normal till I sign in, then it doesn't update "cart" contents or show account holders name or list any "Lists" when accessing account saved lists. I have deleted entire history, and all cookies and caches X 3. I Rebooted computer along with a "system command control reset" and still the pages are not loading correctly. Short of reinstalling "Firefox" what more can I do? Are there any "Preference" files or files with specific extensions I can delete? Thank you. Gerard