Lost access to the board i own

I’m using the free version. I created a board a few weeks ago, and shared it with my internship account. I wasn't working in a team, I was solo. Today, I clicked on the board, and a notification popped up, telling me I did not have permission to access that board, and I had to ask it to its owner. But I am the sole owner! I also received a pop-up to create team… after creating a team the board is lost!!
I cant find it anywhere, in the 1 team I created… and I don't have any trash.
This board is extremely important, I have the link, but neither my personal account nor my internship account can access it. 
what to do?