Ionic 4 - Tabs, icon svg don't change color

I use Ionic 4
And created new icons in SVG for the Tabs, but the icons SVG, not change color.

What I can do?

You haven’t shown us how you are trying to change the color, so it is hard to help.

Have you read this tutorial from Joshua Morony…

…or this tutorial from Ralph’s Blog…

Ref: Theming your Ionic 3 App - Bespoke SVG icons