On the automorphism groups of some nilpotent 3-dimensional Leibniz algebras

Let $L$ be an algebra over a field $F$ with the binary operations $+$ and $[,]$. Then $L$ is called a left Leibniz algebra if it satisfies the left Leibniz identity: $[[a,b],c]=[a,[b,c]]-[b,[a,c]]$ for all elements $a,b,c\in L$. The structure of the automorphism group of $3$-dimensional Leibniz algebras, which have nilpotency class $2$ and a one-dimensional center, is studied.