Why my device root failed

My device model is Primo Ef4+. But my device company is not supporting my device.Becouse of this my device faild to root . so what can i do now?

[emoji137]
First, why do you want to root it?

Second, was the rooting method you found specifically for your device, running your version of Android? If not, that would be why it failed. Rooting has to be figured out for each model phone, for each version of Android that's available for it. (All devices are different, and as soon as someone figures out how to root a particular version of Android on it, the manufacturer patches the hole that allowed that way of rooting in the next version.)