How to change password on this device
Check out the user guide for the exact steps.
In a nutshell you will have to look up the IP address of the 4G Router from a device that is already connected to it. Then enter the IP address of the 4G router into a web browser and log into the routers admin page. From there you will have to navigate around the menus to find either the WiFi or Admin password areas to submit your changes.