How to make fixed camera movement?

Question

Unity

I'm making a scene in which I could move the camera with my finger (mouse), while having borders.
I wrote such an example (code below), the problems are as follows:
After I removed my finger, the camera moves for a fraction of a second, but I would like it to be fixed, but it slides...
And the screen turns over, how to make it fixed?

If there are already ready-made honed sources of camera movement, then if you can link ...

Below is the code I am currently using:

using UnityEngine;

[DisallowMultipleComponent, RequireComponent(typeof(Camera))]
public sealed class CameraControl : MonoBehaviour {
    [Range(0, 20f)]
    public float moveSpeed = 5f;
    [Range(0f, 5f)]
    public float sensitivity = 5;
    public bool isDragging { get; private set; }
    public new Camera camera { get; private set; }

    private Vector2 tempCenter, targetDirection, tempMousePos;
    private float tempSens;

    private void Start() {
        this.camera = GetComponent<Camera>();
        }

    private void Update() {
        UpdateInput();
        UpdatePosition();
        }

    private void UpdateInput() {
        Vector2 mousePosition = Input.mousePosition;
        if (Input.GetMouseButtonDown(0)) OnPointDown(mousePosition);
            else if (Input.GetMouseButtonUp(0)) OnPointUp(mousePosition);
                else if (Input.GetMouseButton(0)) OnPointMove(mousePosition);
        }

    private void UpdatePosition() {
        float speed = Time.deltaTime * this.moveSpeed;
        if (this.isDragging) this.tempSens = this.sensitivity;
            else this.tempSens = Mathf.Lerp(this.tempSens, 0f, speed);
        Vector2 newPosition = this.position + this.targetDirection * this.tempSens;
        if(newPosition.x>10) newPosition.x=10;
        if(newPosition.x<-10) newPosition.x=-10;
        if(newPosition.y>9) newPosition.y=9;
        if(newPosition.y<-9) newPosition.y=-9;
        this.position = Vector2.Lerp(this.position, newPosition, speed);
        }

    private void OnPointDown(Vector2 mousePosition) {
        this.tempCenter = GetWorldPoint(mousePosition);
        this.targetDirection = Vector2.zero;
        this.tempMousePos = mousePosition;
        this.isDragging = true;
        }

    private void OnPointMove(Vector2 mousePosition) {
        if (this.isDragging) {
            Vector2 point = GetWorldPoint(mousePosition);
            float sqrDist = (this.tempCenter - point).sqrMagnitude;
            if (sqrDist > 0.1f) {
                this.targetDirection = (this.tempMousePos - mousePosition).normalized;
                this.tempMousePos = mousePosition;
                
                }
            }
        }

    private void OnPointUp(Vector2 mousePosition) {
        this.isDragging = false;
        }

    public Vector2 position {
        get { return this.transform.position;}
        set { this.transform.position = new Vector3(value.x, value.y, -10f); }
        }

    private Vector2 GetWorldPoint(Vector2 mousePosition) {
        Vector2 point = Vector2.zero;
        Ray ray = this.camera.ScreenPointToRay(mousePosition);
        Vector3 normal = Vector3.forward;
        Vector3 position = Vector3.zero;
        Plane plane = new Plane(normal, position);
        float distance;
        plane.Raycast(ray, out distance);
        point = ray.GetPoint(distance);
        return point;
        }
    }