Using SAB behind a proxy

SAB 9.0.1

I am having trouble building an AAB on our office network.
I presume it is our proxy.
Does anyone have experience with setting up SAB to work with a proxy?

I have set the Build Settings to :white_check_mark: Use compiler offline.
I am getting the error:

> Task :uploadCrashlyticsMappingFileRelease FAILED

FAILURE: Build failed with an exception.