Solved
Error sending a marketing campaign via API
I'm trying to send a marketing campaign via API, but I'm getting the following error: There is already a batch execution in progress , please try again after sometime.

I'm trying to send a marketing campaign via API, but I'm getting the following error: There is already a batch execution in progress , please try again after sometime.

That's weird. Just a thought, have you tried the same thing in a different sandbox? If the problem persists, I recommend opening an Adobe support ticket to investigate the issue.
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