Translation:It is on the bottom left.
Two reasons: に is a particle that indicates ̣(among other things) a location, and あります is a verb for "to be" that usually indicates where something is. To specify what something is, you don't need the particle, and you use the other (often auxiliary) "to be": です.
Would using 左下にです be acceptable too? or can you only use あります when it's a location?
あります／います are used to say that something exists,. "Thing exists at this place" is how you say where something is in Japanese (in my experience anyway - definitely on Duo!)
です is used for describing things, their state. In a lot of languages that would include their location ("thing is over there"), but that property just happens to be phrased in terms of existence in Japanese
These translations have MANY correct translations. Because DL is so picky with the answers this feels a bit like a guessing game.
Also, the Japanese sentence doesn't contain a word for "located" - it just "is" on the bottom left.
When I Google translate "It is down and to the left" to Japanese, I get, 「(それは)左下にあります」
In normal speech it comes out pretty short, like shda. You hear that kind of thing a lot - すこし as skosh, です as dess etc