DIAGNOSIS The Smart Schedule or "Adaptive Recovery" feature is active and overriding temperature changes.
FIX Disable the schedule immediately from the thermostat. Press the Menu button, select "Schedule," then choose "Schedule Type" and set it to "Manual (No Schedule)." This stops all programmed changes. To also stop the system from pre-heating/pre-cooling to reach a scheduled temp, go to Menu > Preferences > Adaptive Recovery and turn it OFF.
IF THAT DIDN'T WORK The mobile app might be pushing a schedule or "Away" mode. Open the Lux app, tap on your thermostat, and ensure the "Schedule" icon is greyed out and "Away" mode is not active. Log out and back into the app to refresh its connection.
HEADS UP Even in "Manual" mode, the thermostat will still enforce any temperature limits you set (like a Heat/Cool range). Check Menu > Preferences > Temperature Limits if you feel restricted.