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Alternatively, if you are using Chrome on Windows, you may want to try logging in to ClassDo with Microsoft Edge.
Check that the code has been sent to the correct email address. Check for typos such as misspellings or spaces. If you have entered the wrong email address, select Back to re-enter your email address.
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The verification code email may have been sent to the spam or junk mail folder of your email account. Check your spam folder for an email from ClassDo.