rigid body can rotate but will not move

Hello Unity forums (: I am trying to build a vuforia AR game. I followed this guide: https://www.youtube.com/watch?v=khavGQ7Dy3c And succeeded in making it fully functional, with the character walking around(using .velocity) and rotating to face the direction it moves in(using .transform.eulerAngles). However, once I swapped out the character model for a different model(In my case, a beating heart), the replacement model could still move around but could no longer rotate. I tried changing the model scale (.transform.localScale) but that didnt work either. It seems that the rb.velocity still functions normally but not the rb.transform.localScale or rb.transform.eulerAngles methods. I remembered to attach a rigid body component to the new model and also to drag them into the appropriate inspector boxes. Please send help i am out of ideas. Here is my code, just in case yall wanna look at it. Note that there are some really lame questionable things I did in the code like converting a byte into a string then into an int then into a float. But for now I need to solve the most pressing issue which is the transform not working.

thank you so much for your help ((':

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 using UnityEngine.UI;
 
 public class overseer : MonoBehaviour
 {
     public Text txt;
     public GameObject character;
     public GameObject SpawnPoint;
 
     public GameObject Plane;
 
     public Rigidbody rb;
     public Animation anim;
     byte[] BLEin = new byte[4]{0,0,0,0};
     int inInt;
     float inFloat;
     string inString;
     public textChanger00 textChanger00;
 
     float x = 0;
     float y = 0;
    // float z = 0;
 
     float angle;
 
     
     // Start is called before the first frame update
     void Start()
     {
         rb = character.GetComponent<Rigidbody>();
         anim = character.GetComponent<Animation>();
         textChanger00 = GameObject.FindObjectOfType<textChanger00>();
        // character.transform.position = new Vector3(0f,1f,-6f);
        // rb.transform.position = new Vector3(0f,0f,0f);
     }
     void FixedUpdate()
     {
         Vector3 movement = new Vector3 (x,-0.05f,y);
         rb.velocity = movement * 4f;
     }
 
     // Update is called once per frame
     
     void Update()
     {
         BLEin = textChanger00.getBytes();
         //inFloat = System.BitConverter.ToSingle(BLEin,0);
         //inInt = System.BitConverter.ToInt32(BLEin,0);
         //Debug.Log(System.BitConverter.getBytes(BLEin));
         //inInt = int.Parse(BLEin);
         //txt.text = System.Convert.ToBase64String(textChanger00.getBytes());
        // txt.text = Encoding.Default.GetString(textChanger00.getBytes());
       // txt.text = System.BitConverter.ToString(textChanger00.getBytes()); //works!
        // txt.text = System.BitConverter.ToString(BLEin); // this also works
 
         inString = System.BitConverter.ToString(BLEin);
         inInt = System.Int32.Parse(inString, System.Globalization.NumberStyles.HexNumber); // aw shit this works. its stupid but it works
         inFloat = inInt/10;
         //txt.text = inString;
 
         //Debug.Log(inInt);
 
         //TEST CODE START HERE
        // Vector3 scale = new Vector3 (inFloat,inFloat,inFloat);
        // rb.transform.localScale = scale;
         //TEST CODE END HERE
 
 
 
       //okay so this works. the in the byte array, when working from 0 to 5, only 0th index changes 
        
        switch (BLEin[0])
        {
            case 1:
             txt.text = "UP";
             y = 1;
             x = 0;
             
             angle = 0;
           //  anim.Play("walk");
            break;
 
            case 2:
             txt.text = "DOWN";
             y = -1;
             x = 0;
             
             angle = 180;
            // anim.Play("walk");
            break;
 
            case 3:
             txt.text = "LEFT";
             x = -1;
             y = 0;
             
             angle = -90;
           //  anim.Play("walk");
            break;
 
            case 4:
             txt.text = "RIGHT";
              x = 1;
             y = 0;
             
             angle = 90;
           //  anim.Play("walk");
            break;
 
            case 5:
             txt.text = "A";
            break;
 
            case 6:
             txt.text = "B";
             x = 0;
             y = 0;
             
 
            break;
 
 
            default:
             txt.text = " ";
             x = 0;
             y = 0;
             
           //  anim.Play("idle");
            // rb.velocity = Vector3.zero;
            // rb.Sleep();
            break;
        }
 
 
 
        Vector3 movement = new Vector3 (x,0,y); // no y component because not moving up and down
         
         rb.velocity = movement * 4f;
         rb.transform.eulerAngles = new Vector3(0,angle,0);
 
         if (rb.transform.position.y < Plane.transform.position.y - 2)
         {
             rb.transform.position = SpawnPoint.transform.position;
 
         }
         
 
 
 
     }
 
     
 }