There are no "sprints of the same name", it's all one sprint. Sprints don't belong to projects either, they're cross project. I suspect what you're seeing is that "sprint X" is appearing on more than one board and maybe in more than one project because it includes issues that are in different boards/projects.
A sprint can span more than one project, if multiple projects are included in the board on which the sprint was created. A sprint is visible on all boards that contain issues belonging to the sprint.
@Jack Graves [AC] first caught our eye with his incredible breakdown of what, in his opinion, can make or break a Jira software implementation. (Read his thoughts on this thread)! In this follow...
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