Opening Modal popup on Ajax form submission

It is not right

location.href = "#modal";

when you need to change hash you need to use window.location.hash=”modal”

but you have another problem!

You need to initialize your plugin and use its api

Instead of this location.href = “#modal”; you need to use:

var inst = jQuery('[data-remodal-id=modal]').remodal(); 
inst.open()