Hi Lê,
Thank you for reaching out. There are a few possibilities for what you have referred to. One scenario is that you are linking your manager account to the client customer account by extending an invitation. Another scenario is that you are granting a user email with a certain access level to the Google Ads account via the Google Ads UI. However, I doubt there is an email notification to inform you that the customer has accepted your invitation for the former one but you would get email confirmation for the latter one.
Thanks and regards,
Xiaoming, Google Ads API Team
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| Xiaoming |
| Google Ads API Team |
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