When I went to use my phone I found out my buttons at bottom of my phones are gone. So I can't go back and I can't use it efficiently. What should I do? Any advice? . Thank you in advance.
Probably disappeared after the update today.
Swipe up from the bottom to bring them up and tap the little dot at the bottom left of the bar. This will "lock" it into place so they won't disappear again.
And once you have it back, you can turn off that feature. Settings > Display > Navigation bar > Show/hide button. Then you won't toggle it accidentally.
As mentioned, swipe up from the bottom of your screen. Double tap the dot on the left side. This will lock it in place. Double tap the dot again to enable auto-hide.