Unity Gravity not working fine

Question

i made an animal and got an animal script. But if my Animal turns around it falls down. I tried to make it kinamatic but he dont had any gravity anymore

using System.Collections; using System.Collections.Generic; using UnityEngine;

public class Animal : MonoBehaviour { public float movementspeed = 3f; public float rotspeed = 100f;

 private bool iswandering = false;
 private bool isrotleft = false;
 private bool isrotright = false;
 private bool iswalking = false;

 private void Update()
 {
     if (iswandering == false)
     {
         StartCoroutine(Wander());
     }
     if (isrotright == true)
     {
         transform.Rotate(transform.up * Time.deltaTime * rotspeed);
     }
     if (isrotleft == true)
     {
         transform.Rotate(transform.up * Time.deltaTime * -rotspeed);
     }
     if (iswalking == true)
     {
         transform.position += transform.forward * movementspeed * Time.deltaTime;
     }
 }
 IEnumerator Wander()
 {
     int rottime = Random.Range(1, 3);
     int rotwait = Random.Range(1, 4);
     int rotatelorR = Random.Range(0, 3);
     int walkwait = Random.Range(1, 4);
     int walktime = Random.Range(1, 5);


     iswandering = true;

     yield return new WaitForSeconds(walkwait);
     iswalking = true;
     yield return new WaitForSeconds(walktime);
     iswalking = false;
     yield return new WaitForSeconds(rotwait);
     if (rotatelorR == 1)
     {
         isrotright = true;
         yield return new WaitForSeconds(rottime);
         isrotright = false;
     }
     if (rotatelorR == 2)
     {
         isrotleft = true;
         yield return new WaitForSeconds(rottime);
         isrotleft = false;
     }
     iswandering = false;
 }

}