please consider Alternatives to mailchimp...
"Mail chimp has become unreliable because they can decide for some reasons that your manually created campaigns are a scam. They block peoples account without giving any warning. They block everything including the API used in sending emails. Mail chimp has joined the gang of companies that treats you as if they are doing you a favor even though you are a paying consumer."
https://medium.com/@bjornvhauge/mail-chimp-is-shutting-cryptocurrency-accounts-but-there-are-alternatives-8d9a02347281