Form data not being saved

I fill out a specific online form on a regular basis. When I used Chrome several months ago it always remembered my form data. But no matter what setting I set I cannot get this to work on Firefox. Under Privacy & Security I've set History to Use custom settings for history: Remember browsing and download history enabled Remember search and form history enabled Clear history when Firefox closes disabled I have also checked antivirus, antispyware, firewall, and privacy programs are not interfering. I do have a VPN but only use this when using online banking.