I don't ususally use Google Fonts so this may not be a big help, but here are some possible reasons / tips:
1) check to see if the Text object has the Font property set to whatever font you want.
2) It could perhaps be an issue with Google Fonts. I like to use FontStruct, you can make and download fonts and import as a .ttf file, and I've never had issues with it.
3) This isn't likely, but it could be an issue with the editor or the device. Maybe the editor doesn't preview correctly?
Maybe share a screenshot of more details to make it easier to find the problem.