You can reset the limit here
https://filterspoints.crm-onebox.com/app/employer/online/ there is Reset user blocking
regarding login - if you added these users to the site for access via onebox id, then check if they are in access control
If you logged in with a username and password, check if you have changed your passwords to new ones.
Also provide the login with which the problem is because it is not clear at the moment.