Continuing rotation of circle from new point on screen by touch

Hello,I have circle in my game that i use to rotate while draging my finger on the screen.When i take finger off the screen,and then drag from another place,the circle should continue rotating from previous rotation instead of instantly changing rotation.It kinda works but my problem is that sometimes - I can't tell when that happens exactly,the circle jumps to new rotation instead of continuation.Can someone tell me where i have error in my script?

Here's the exact part of the script :

 if (Input.touchCount > 0)
          {
  
              Vector3 pos = Camera.main.ScreenToWorldPoint(Input.GetTouch(0).position);
              Vector2 touchPos = new Vector2(pos.x, pos.y);
              if (Input.GetTouch(0).phase == TouchPhase.Began)
              {
                  startAngle = Mathf.Atan2(touchPos.y,touchPos.x) * Mathf.Rad2Deg;
                  if (startAngle <= 0)
                  {
                      startAngle += 360;
                  }
              }
              angle = Mathf.Atan2(touchPos.y, touchPos.x) * Mathf.Rad2Deg;
              if(angle < 0)
                  angle += 360;
              distanceAngle = startAngle - endAngle;
              angle -= distanceAngle;
              if (angle < 0)
                  angle += 360;
              else if (angle > 360)
                  angle -= 360;
              if (Input.GetTouch(0).phase == TouchPhase.Ended)
              {
                  endAngle = angle;
              }
              
              circle.rotation = Quaternion.Euler(0f, 0f,angle);