Ignore requests for billing information
As noted in the Account Creation Guide, you must skip the billing section in your account setup. After you create your AdWords account, you might see messages in your account or via email requesting that you submit billing information. Please ignore these requests. Because nonprofits create accounts through the same interface as paying advertisers, you may see these alerts until we have activated your account for Google Ad Grants.
Once you build your AdWords account and submit your AdWords Customer ID via the Google Ad Grants application, our team will review the account and activate it if it meets our guidelines. At this point, the billing alerts will disappear from your AdWords account.