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Check the email address of the contact and the email address in the email message


It happens once and a while the email address saved in Tamago-DB is slightly different than the one used to email the contact through your mailbox. It might contain a dot, hyphen, underscore or a character might have been misread : o and 0, i and l, ...


For example, Gmail ignore dots in the email address : 


If someone accidentally adds dots to your address when emailing you, you'll still get that email. For example, if your email is johnsmith@gmail.com, you own all dotted versions of your address:

  • john.smith@gmail.com
  • jo.hn.sm.ith@gmail.com
  • j.o.h.n.s.m.i.t.h@gmail.com


Source : https://support.google.com/mail/answer/7436150?hl=en


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