Every username on Semaphore is unique. Make sure that you use only alphanumeric lowercase characters while choosing your username. Same rules apply while choosing the name for Semaphore organization - it is also one of a kind and you must use alphanumeric lowercase characters. Please note that account username and name of the Semaphore organization cannot be the same.
Email address on Semaphore also needs to be unique. You cannot create two Semaphore accounts with the same email address. Also, two users cannot add (and verify) the same address to an existing account. You can read more about it here.
Password must contain minimum 6 characters and that is the only requirement for password on Semaphore. Which combination of characters will you use is completely up to you.
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