I’m getting this message when I try and send an email: "Your message wasn’t sent because there’s a daily message limit. But don’t worry…

I'm getting this message when I try and send an email: "Your message wasn't sent because there's a daily message limit. But don't worry, we saved it in your Drafts folder. To increase the limit, verify your account." Then when I click on the "verify your account" link and enter my mobile number, it keeps coming up with a message saying something like we can't do this at the moment, and so the cycle continues, on and on, and I still can't send the email! Can anyone suggest what I can do to sort this out? Thanks.