Score Points and Animation

For my game the player is supposed to fulfill different little tasks, like collecting 5 bags of gold, and when he collects these 5 items I want to give the player a star as reward and I want an animation of a star rotating around itself in the middle of the screen. The counter for the first items works so far, and the counter for the stars is displayed but doesn't add up when supposed to. Also, I created a star and the animation in 3DS max and imported that into Unity, I named the animation "Drehen", how can I get it to play when the player actually gets a star? This is my code atm, thanks for any help!

 using UnityEngine;
 using UnityEngine.UI;
 using System.Collections;
 
 public class SammelnCounter : MonoBehaviour {
 
 
     public Text sackZaehler;
     private int zaehler;
     public Text sternZaehler;
     private int sternencounter;
     Animator anim;
 
     void Start () {
 
         zaehler = 0;    
         sternencounter = 0;
         SackZaehlText();
         anim = GetComponent<Animator>();
     }
 
 
     void FixedUpdate() {
         
     }
 
     void OnTriggerEnter(Collider other) {
 
         if (other.gameObject.CompareTag("Sack")) {
             other.gameObject.SetActive (false);
             zaehler = zaehler + 1;
             SackZaehlText();
             
         }
     }
     
     void SackZaehlText() {
 
         if (zaehler >= 5) {
             sternencounter = sternencounter + 1;
             sackZaehler.text = "Quest abgeschlossen!";
             Animation.Play("Drehen");
         } else {
             sackZaehler.text = "Goldsaecke: " + zaehler.ToString();    
             sternZaehler.text = "Sterne: " + sternencounter.ToString();
         }
     }
 }