Are you using the app or a full browser, phone or computer? I tried it on my system, Windows Chrome, and it works just fine. I find that many of the drop down menus do not work well on a phone or tablet.
2017 Phaeton 40IH XSH Maroon Coral - Power Glide Chassis with IFS
Previously '15 Tiffin Allegro RED 38QRA and '06 Itasca Sunrise 35A
'16 Jeep JKU Wrangler Sahara or '08 Honda Goldwing