@Nikitos007 - Because you were able to delete the board, you are definitely the board owner and can restore it, as long as you still have the board link. If you are using a browser, probably the fastest way to find the link is to open your browser history (Ctrl-H if on Windows and using chrome, Edge, or Firefox) and then search for the board name.

When you try to open the board, as thee board owner, you will see a “restore the board” action, as shown below:

Another option is to pay $10 for one for a Starter Plan by using the Upgrade action:

After you have upgraded, you will have the Trash bin and can restore the board:

NOTE: If there are other team members, and you do not want to pay $10 for each member, you will first need to deleted them all from the team – you should go the the Users page and note everyone who is currently there (a screenshot could suffice):

Later, once you have recovered the board, you could cancel your subscription and add the team members back: