I vaguely remember the title of this novel. that I remember in the illustration mc met with their two noble daughters around 15-17 years (they were both saved by mc?) NB: not isekai smartphone
? You mean his daughters? Or just daughters of nobles? Were they saved together or different times? Need more info to proceed.
Though your description is not clear.. But probably this one.. https://www.novelupdates.com/series/wortenia-senki/