If a user attempts to login with an incorrect password three times it will cause the DotApprove account to be locked. Once an account has been locked it will need to be unlocked by an admin user. 

Unlocking an account can be done quickly via the User Management section.

Step 1: Find the locked out user within the User Managemen' section on the home tab. The locked column will say Yes, to show the account is locked. 

Step 2: On the drop down beside the users email address select 'Edit User'. 

Step 3: Deselect the Locked box and click Save. The user has now been unlocked.