Why doesn't the thirdpersoncharacterblueprint have axis input mapping for left and right movement?

So I while i was working on the thirdpersoncharacterblueprint when i compiled all the input axis where broken and the error said it could not reference those axis. So I went into input and noticed that my axis mappings werent there, (dunno if they were there before or not) and then i added the exact names of the nodes respectively. On Play everything was fine except i couldnt move my character left and back, only foward and right. I checked my blueprint and it doesnt even have a left and back inputaxis.

What i want to know is why i could move left and back before even though there was never a left and back node within the blueprint? Do i have to add those inputs now just because something went wrong?

ok so i opened up another third person character blueprint and checked the project settings > input > axis mappings and noticed that there was a lot of stuff there i probably deleted it on accident i guess. anyways it also showed me that forward and right use negative values to create the back and left movements respectively.