Endomorphism ring of $\mathbb{Z}/n\mathbb{Z}$. (in reference to elliptic curves over a ring)

Question

I know for the group $E(\overline{\mathbb{F}_p})$ where $p$ is prime we have the Frobenius endomorphism, say $\phi$, satisfies the equation $(\phi^2 - [t]\phi + [q])P = [0]P$ in the endomorphism ring End$(E)$, where $[n]$ is the multiplication by $n$ map.

So I'm wondering for an elliptic curve over a finite ring, when we have the group of points $E(\mathbb{Z}/n\mathbb{Z})$, we don't have Frobenius endomorphism nor do we have any other endomorphism besides the multiplication by $n$ map right?