If a Google Font is not working in the WordPress Customizer, it is because the font-weight is not supported.
How to Fix: Select the Different Font Weights
Switch the font weights to get the font to load properly.
Version 3.19 & Up

Version: 3.18 & Below

You need to test the different font weights to see what is available.
So, if the font you select does not look correct, try selecting a different font weight.
You can visit https://fonts.google.com website to see all the font weights that are available for each font.
Version 3.18 & Below Notes
How to Fix: Click the Numbers 1 to 4
The numbers represent different font weights, and some fonts do not support multiple font weights.
What the Numbers Above Mean: 1 = Light , 2 = Normal, 3 = Bold , 4 = Bolder
Not All Fonts Have Multiple Font Weights. So, you may only be able to select 2 ( Normal ) for the font to work.
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