Download the GoodAccess WordPress plugin.
Log into your WordPress administration and go to Plugins -> Add New.
Search for the GoodAccess plugin and click Install Now and Activate.
Go to Installed Plugins and click on Settings.
Make sure you are connected using the GoodAccess Client App.
Add your WordPress Admin (your_WordPress_site_URL/wp-admin) as a new system in the GoodAccess Control Panel and click on Get Plugin Activation Code
Paste the generated Plugin Activation Code into Plugin settings in your WordPress administration and click on Activate Protection.
You should now see a status PROTECTED.
Congratulations! From now your WordPress Admin page will be protected and accessible only by your team connected through the GoodAccess Client App.
NOTE: In case if you need to disable the protection and access your WordPress Admin without GoodAccess you can deactivate the plugin in GoodAccess Control Panel -> Systems. In case of any issues with the restricted access, you can always bypass it by FTP by renaming the plugin folder: wp-content/plugins/samohyb-goodaccess.