why the object behave like ease-out even I set the ease to "Linear" using tween

Hi everyone,
I’m new to Phaser, I try to animate one of my object from ouside the sceen to the center using tween and I want it behaves as linear with below code, but it still behaves like ease-out, anyone could help me out?

    targets: this.prize,
    duration: (range.end - range.start) * 1000,
    x: this.width / 2,
    ease: "Linear", 
    // ease: "cubic-bezier(0.0, 0.0, 0.0, 0.0)", <--- I tried this

It doesn’t look like linear ease?