We have a series of similar workflows across multiple sites. The simplest of these is a single action: an email is sent when a list item is created. We have found on a few of these workflows (the simple one included) that the workflow repeatedly sends the email to the entire recipient group. This continues to happen until the workflow is manually terminated.
The same workflow exists on other sites (literally an export/import) and they work correctly.
For context, the recipients for the email are almost always the default members/owner/visitors groups that belong to that site. The list item has a recipient field where this is specified.
Any help would be appreciated. We are currently working with Nintex Support and Microsoft to understand the issue, but want to rule out anything simple on our side.