Low Data Mode is an iOS setting that reduces any app's ability to use data in background mode.

As the GoCarma app activates automatically to confirm your HOV status when you travel in a TEXpress Lane during weekday peak periods, enabling this setting may cause you to miss out on receiving HOV toll discounts.

Therefore, if you have enabled Low Data mode in your Settings, please ensure that you undo this if you wish to qualify for HOV toll discounts. You can change this setting by opening the Settings app, selecting Cellular, selecting Cellular Data Options, and selecting Standard.