We get this question a lot. Sounds like you have the Accessibility menu enabled.
As you don't say what device you have, here's where to go based on a Pixel 2 XL (the device I have) - Open Settings > Tap Accessibility > scroll to Accessibility Menu and tap it > slide the switch to the left for Use Service.
As enabling this requires a verification I'm shocked so many people end up with it "mysteriously" enabled.
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