Maps don't work in a custom build (even after adding API key)

I'm trying to answer a "Line" type question on a custom build of the github code, but there's no map appearing even though I added my API key in the code.
Any ideas?

Hi @amalm
Did you do everything according to our Readme

If so are you getting any logs/errors in Android Studio that you could share?

Thanks @Grzesiek2010 for the quick reply.
My developer figured it out, it was an issue with the set of APIs we had.
Now it's fixed.