Each time you login from a new IP address it triggers the suspicious warning. Usually that would only happen when you change location and actually log in from somewhere else, but if your ISP gives you a dynamic (not fixed) IP address it will do this every time they change it.

The solution to this is to add a one time password to your account. Either as the free smartphone app (iPhone/Android) or as a physical token where you push the button (there is a small cost for this to cover the token). Having that on your account disables the IP address check AND you get a free teleport of your choice in game (which you can change as well!)