In most cases, problems with the website are caused by browser issues, a specific configuration on your computer that can be hard to track down. Many factors can be involved, including but not limited to browser customization, add-ons, pop-up blockers, auto-fill settings, security settings, and other security software.
We cannot determine which of these many factors may be causing the behavior you're experiencing, however often the issue can be resolved simply by trying another browser. Using a browser you don't normally use, which will have less customization, also means you don't have to change the settings on your favorite browser.
You can also try private or incognito browsing mode in your existing browser. This mode does not use your cache and other settings. There will be a menu command, or you can use these keyboard combinations: