Card no longer opens

[Magnet Formula - Area Web 1]

Hi everyone, I'm having an issue with a tab that I've never encountered before. Suddenly, it's impossible to open. If I click on it, the attached screen appears, saying "Tab not found." I also noticed something strange in the list, as the tags that were activated within the tab also seem to have disappeared.

[Valerie Knapp]

Hi @Magnet Formula - Area Web 1 , welcome to the Atlassian Community and thanks for your post.

Have you already tried these things - https://community.atlassian.com/forums/Trello-articles/Can-t-find-your-Trello-cards-Try-these-troubleshooting-tips/ba-p/2947608 ?

Is it possible the card has been moved from another board and lost these attributes in the process? https://support.atlassian.com/trello/docs/moving-cards-or-lists/ 

Please let us know if you are still having this issue so we can find other troubleshooting support.

Best wishes

[Magnet Formula - Area Web 1]

Hi Valerie, thanks for your reply. The first article you linked refers to a tab that's not even visible in the list, while mine is visible with all the others, but when I try to open it, the error message "Tab not found" appears.
I also tried in April from the context menu, but the result is the same. I added a label, which I see in the closed tab, and I moved the tab from one list to another, but these actions didn't solve the problem either.
It's a tab I've used for a long time without any problems, and once I finished working, I moved it to the current board—an operation I do constantly with many other tabs, without ever encountering this problem.