Hello, I have this package installed in my Org and stop working Yesterday, any idea what could be the reason?

Hi, @Yadira Avila Espinosa Maybe the package is expired. You can check the status "Expired" or "Active" in "Installed packages" [Setup-> Search "Installed packages" in "Quick Find"]. Or, maybe somebody has removed a permission set that is part of the package from the affected users.