@Balázs Bányai - If by "wrong team" you mean the board's you wanted to work on are in another team, if your Miro account profile is a member on both teams, you could move the board's that you are the owner of to the team that you upgraded by using the ellipsis menu (to the right of the board, from your dashboard) and use the "Move to account" option to move the boards to the team that you just upgraded. I would take screenshots for you, but I can't currently get up to get to my computer:

 And if you upgraded a team that is a part of a completely different Miro team and the steps above won't work, you will need to contact Miro support, so they can work with you to apply the upgrade to another team. You can contract them here: Submit a request – Miro Support & Help Center

Hey @Balázs Bányai,

As Robert mentioned, it's better to get in touch with support to find the right solution in your particular case, however, it isn't technically possible to transfer the subscription from one team to another. We'll be happy to offer you other solutions after taking a look at your profile and subscription which can be done only once the ticket is submitted.