If the survey"s Auto-advance mode is enabled, the "Next Question" button will be displayed for questions that aren"t supported with Auto-Advance. To remove the "Next Question" button, you can disable the Auto-advance option.
Steps: Go to Edit >> Design >> Survey Layout >> Settings >> Disable Auto-advance.
Screenshot: https://prnt.sc/WEYa4lahDBQB
Help file: https://www.questionpro.com/help/auto-advance.html