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                   The mail system

<james@daysix.co>: host aspmx.l.google.com[142.250.145.27] 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, please visit 550 5.2.1
    https://support.google.com/mail/?p=ReceivingRatePerm
    l5-20020a50d6c5000000b0043bc31ac7d0si1141475edj.211 - gsmtp (in reply to
    RCPT TO command)