Hello, there. So you’re reading this page because you are stuck in a continuous loop of the page asking you to select a user without actually letting you select the user you want. Absolutely no worries, as these errors are easy to solve!
Once the access has been granted to all the users of the domain, please head over to the import portal again to start your migration. It should be working fine now!
Another option is that the admin of the account hasn't installed the migration tool yet! If this was the case, please take a look at this support article which will give you detailed information on how to install it!
If you´re still having any problem after trying these steps, feel free to contact us at help@cloudasta.com and we will be happy to help you out!