Motion Tracking does not work for the total duration of the clip

Hi,

First of all, I already used motion tracking in Premiere Elements a couple of months ago and it worked well. Now, it does not. First time, the video was taken by Iphone XR and this one - by Iphone 7.

I have a 10 seconds clip (my test clip), where my daughter moves the ball from one side to the other one (back and forth) for 10 seconds. I want to follow the ball and attach a NOT-anumated object to it from the graphics panel, for example, Panda from the Baby category. I track the ball (the program does it very quickly) and attach Panda to it. The tracking happens only for 2 seconds and then the object (Panda) disappears. I thought the problem is the length of Panda object (as it shows shorter than the clip), but it is not an animated object, so it should last for the duration of the clip. I tested by tracking the object (ball) and playing the video before attaching Panda to the ball, and the yellow rectangle only moves for a couple of seconds and then disappears, like it gets detached from the ball. Therefore, I think the problem is in the Motion Tracking tool itself, and not the object I am attaching. Can you let me know what the issue could be.

Thank you!