CentOS 7.9 - flickering mouse cursor with a black box near it

I have a centos7.9 that has a windows 7 Virtual machine installed on that centos. when I start the virtual Machine, it shows a black box near the cursor and the mouse is flickering. I have tried to change the the video card from Dell NVIDIA Quadro K620 to two Dell GeForce 310

Any idea on how to get rid of that black box near the cursor?