Hello, I see there is way to limit concurrency for a task using tags. But what about flows? How to make sure the same flow (or the same deployment) does not run concurrently?

On Prefect 2, you can set a concurrency limit at the Work Queue level from the CLI or the GUI. If just one deployment is using a Work Queue with a concurrency limit of 1 would that accomplish your goal?

Yep, that would achieve a goal, I am just using one queue for all tasks