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<Professorfayette2020(a)gmail.com>: host
gmail-smtp-in.l.google.com[108.177.119.26] said: 550-5.2.1 The user you are
trying to contact is receiving mail at a rate that 550-5.2.1 prevents
additional messages from being delivered. For more 550-5.2.1 information,
go to 550 5.2.1
https://support.google.com/mail/?p=ReceivingRatePerm
x20-20020a05640226d400b005548f93eb76si9768439edd.212 - gsmtp (in reply to
RCPT TO command)