FPS remains fixed at 60 fps regardless of the Max Framerate setting

I have a phone with a 144Hz screen refresh rate and I set the Max Framerate in the game settings to 140 fps. However, even after doing so, the fps stays fixed at 60 fps and doesn't increase.

Steps:

1. Go to settings and set the frame rate to 140 or higher

 Expected Result:
I expect the fps to increase to 140 as I set it in the game settings and take advantage of my phone's 144Hz screen refresh rate.

 Observed Result:
The fps remains fixed at 60 fps regardless of the Max Framerate setting, and doesn't take advantage of the phone's 144Hz screen refresh rate.