Difficulty in logging in for my online course

Hello,
I downloaded Firefox was to be able to log into my school's webpage where we have our online teaching modules. And this was after trying to log in via Internet Explorer. For past twenty four hours, I have been trying to log and I have tried all sorts of recommnedations: cleared out the cookies and cache, allowed cookies for that site alone and as well cleared profile and other private data, and also deleted all cookies.sqlite file and cookies.sqlite-journal files, yet I still have been unable to sign in. What else can I do please? :-(