Unless you are paying extra for it, you probably do not have a static IP address so that means it's dynamic (DHCP) so it changes (sometimes as often as daily but that's up to your ISP).
Do the complete unplug everything and plug everything back in and then power up routine. Go through network set up again. Have it select IP address automatically and don't specify it. It will ask for your network password. At that point, it should log you back into your wireless network. Also, you may need to do a power cycle on your dsl modem and your wireless router as well.
If that doesn't fix it, try logitech support. As recently as three months ago, they had specialists available that dealt with the transporter so hopefully still do.
Having said all that, I use ethernet and like it a lot better.