​@Yasushi Kusume You will need to ask a Company Admin of your Miro subscription to reactive the user – more on this here: https://help.miro.com/hc/en-us/articles/360025025894-Deactivated-users#Re-activate-a-user

To find a Company Admin, go to the users page of one of your teams:

And then look for a Users → All users page and filter by Role → Company Admin.