Depending on how you have your browser configured you may experience problems with 'Cookies.'
(If none of the following work for you simply type your problem into Google. You'll very likely find a solution there.)
Chrome:
Click the Chrome menu on the browser toolbar.
Select Settings.
Click Show advanced settings.
In the "Privacy" section, click the Content settings button.
In the "Cookies" section, you can change to your preferred setting.
FireFox:
Click the menu button and choose Preferences.
Click the Privacy menu item at left.
Under History Set Firefox will: to Use custom settings for history.
Select Accept cookies from sites and make sure Accept third party cookies is also not set to Always.
MicroSoft Edge:
Open Microsoft Edge app.
Click on the More actions button in the top right corner and select Settings.
Scroll down the settings and click on View advanced settings button.
Under Cookies, select one of the three options to allow or block cookies.
Safari:
Choose Safari > Preferences, click Privacy, then do any of the following:
Change which cookies and website data are accepted: Select a “Cookies and website data” option: ...
Remove stored cookies and data: Click Remove All Website Data, or click Details, select one or more websites, then click Remove.