In cases where it has been identified that an email address for a learner has been incorrectly entered the best solution is to delete the learner account in Manage Learners without editing the email address. Editing the email address doesn't automatically resend the enrolment email and doesn't update the username which is often the same as the email address.
Deleting the learner will add any unused licenses back onto the parent account so that they are made available again.
The administrator should then add the learner again with the correct details. If an email address is included, this will trigger the sending of a new automated enrolment email to the correct email address, allowing the learner to access the course(s).
Note that deleting a learner will remove access to all their courses and certificates, so this shouldn't be done in cases where learners have any completed, or partially completed courses.