Android Question Gmail API, not working

I am new to using API's. I have gone through the OAuth 2.0 tutorial and got that working just fine within a few hours. I can't seem to get the GMail API to work using the provided zip file for the tutorial. I changed the ClientID to my personal code. The only thing else I changed was the address to where the message was being sent. I have ensured the Gmail API is enabled on the developer's console. I set up my key with the correct package name from the manifest file: "b4a.googlecontacts". Is there something else I am missing here? The error I get is a permissions denied, 403 HTTPS error. I can't figure out why on the POST method I keep getting this error when the message is trying to be sent. I reviewed the API and the syntax is all correct from that point of view. I also know the token part of the request is working.

Here is what the log records:
Getting access token from refresh token...
*** Service (httputils2service) Create ***
** Service (httputils2service) Start **
Token received. Expires: 03/13/2018 17:05:53
ResponseError. Reason: Forbidden, Response: {
"error": {
"errors": [
{
"domain": "global",
"reason": "insufficientPermissions",
"message": "Insufficient Permission"
}
],
"code": 403,
"message": "Insufficient Permission"
}
}
Failed to send mail.
Done!!!