If you think your Gsuite email account is already set up in your Prospect Reach settings but it's still not sending emails, here's a method that you can use:
1. Enable your Gsuite account's 2-step verification.
2. Generate an App password for Prospect Reach.
Note: When you're asked for a name for the app, you can just enter "Prospect Reach"
3. Use that Password in the Email Account (Gmail SMTP) in Prospect Reach.
4. Try to send a test email to any of your existing emails. If the test email got sent out, you've done a great job!