i think you're tt too close to 6 am. the game saves at 6, so i rec you tt to 5:56-ish just to get some cushion time so you can load up and save and quit before the clock hits 6.
however, after reading your post again, i don't think you're actually plot resetting- just tt to almost the next day. to plot reset, tt to 5:56-ish for the reasons i said above, load up, save and quit, and don't open your game until 6. once the time is past 6, open up acnl again, but don't use an existing character! select "new save file" instead, and go through rover's sequence. you'll be on a completely new character, so you have a chance to run around town and see where the villager plotted before you save your game- which makes that plot permanent. hope that helped some :')
if you want a more comprehensive guide on plot resetting (mine was rushed and didn't explain some things fully), i've linked one for you
here. good luck!!