First thing I would do is check the battery. It might need replacing.
Believe me, most mice - mouses ? - do have a battery. A symptom of one needing replacement is as you've described.
I have USB, wireless and laser precision: each has a battery.
Might want to try inserting a new one and see how the mouse, then, functions

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If not the battery, and if the mouse connects to computer via serial port or USB, double-check to make sure that the contact is solid/firm.
If not those things, I'd either run a "repair" or do a clean re-install of the mouse's software. It may be a corrupt driver.
That's the sequence I'd run through.
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".... This world wasn't built for people in wheelchairs ...."
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