Why was your mail merge stopped?
You were sending a mail merge and before it was done it stopped, and the following message appeared:
An unusually high amount of bounces was detected by YAMM, so your mail merge was stopped to avoid Google rate-limiting or deactivating your account.
Check the list of reasons for bounces here: What are bounces? Why do I get bounces?
If none of those concern you, you might have reached your Google account sending limit.
Why is your sending limit lower than you expected?
|You exceeded your daily sending limit
Read this article: I don't have quota left / My quota didn't reset
|You exceeded the limit of 10 recipients being marked as spam
Google temporarily reduces your quota if:
Make sure to follow the basic anti-spam rules: Tips: How to avoid being blocked by Google or spam filters
|Your account is recent and you have sent too many emails too quickly
Google might get suspicious about your activity if, after you created your account, you immediately started to send emails to many recipients.
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