Followed this to a T(at least I think I did). Still getting the following error..
Cannot read properties of undefined (reading 'contactGroupResourceName')
Im not creating a group. I want to add to a group..
Hi there
Welcome to the Community! 
It looks like you’ve reached out to our Support Team about this and they replied today with a suggestion. I’ll share details of the suggestion here in case it’s helpful:
I see that you're looking for some help figuring out why you're running into an error when trying to add a contact to a group in Google Contacts. I totally understand wanting to get to the bottom of this and will do my best to help out here!
Looking at the Zap history you shared, I noticed when checking the timestamps that Step 2 is creating the contact only 3 seconds before the Add Contact to Group step is firing. That might not be enough time for Google Contacts to have fully created the user.
To see if a bit more time would help, I recommend adding a step with Delay by Zapier between the Find/Create step and the Add Contact to Group step. Adding a buffer of 1 minute should suffice in terms of testing.
After adding that delay and publishing the change, please monitor the next run that comes through to see if any errors persist at that point.
If you’ve got any questions regarding their suggestion it would be best to continue the conversation with them over email. If you can’t locate their reply I’d recommend searching your spam/junk folder or searching your inbox for any emails from zapier.com in case. Sometimes their emails can end up in the spam/junk folder by accident.
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