How to use a 1st generation magic mouse with Sequoia 15.5

never used the 1g magic mouse but have you tried to put it into pairing mode?

what the AI says

"To enter pairing mode on a Magic Mouse, you need to turn it off and then back on, ensuring the green light above the power switch blinks to indicate it's discoverable. For a Magic Mouse 2, plugging it into your Mac via a lightning cable will also initiate pairing. 

Here's a more detailed breakdown:

For Magic Mouse (1st generation):

1. 1. Toggle the power switch:
2. Locate the small power switch on the bottom of the mouse and switch it off, then back on.
3. 2. Observe the light:
4. The green light above the power switch should blink, signaling that the mouse is in pairing mode and ready to be discovered by your computer.
5. 3. Pair with your device:
6. Go to your computer's Bluetooth settings and select the Magic Mouse from the list of available devices. 

For Magic Mouse 2 (2nd generation):

1. Connect the cable: Plug the Lightning end of the cable into the port on the bottom of the mouse and the other end into your computer.
2. Turn on the mouse: Ensure the power switch is toggled to the "on" position.
3. Automatic Pairing: The mouse will automatically pair with your Mac via Bluetooth once connected through the cable. 

Note: If you are pairing to a Windows PC, you may need to manually add the device in the Bluetooth settings and follow any on-screen instructions"

from

magic mouse pairing mode - Google-