In typing a document, when i go back by moving the cursor with the mouse, after doing a correction or insertion. sometimes the mouse loses control of the cursor and it stays where i left it last. I revert to using the up and down arrows to return it to the end of the document, and the mouse then recovers control.
I would check mouse batteries, then mouse driver, functioning of mouse on a different system, interference of Bluetooth or mouse Wi-Fi, a minimum of 15% free space on hard drive, operating system is up to date and is not waiting to reboot following an upgrade, adequate RAM
Optical mouse? Check there isn’t a hair or some dust obscuring the optical sensor on the bottom of the mouse…
I have 4 cats and there is usually a hair from them mucking up the optics when the pointer doesn’t move or behaves intermittently .
Some paper fluoresces enough to confuse a mouse. A colleague had a mouse mat with 3D hologram; that would freeze the cursor very effectively.