I’m also a user of this plugin who has had issues with links being improperly redirected with plugin version >= 3.0.

We rolled this plugin back to 2.8.0 and it fixed our issues. I’d recommend you do this until the developer is able to provide a fix.

From us debugging, we’ve found that on version >= 3.0, any page that implements a custom permalink, ex. /pageA custom permalink of /page, if we add an associated dependent of that /page, like /page/detail through formidable forms or another plugin, it won’t work anymore, but that behavior is supported on 2.8 and lower. To access that /page/detail without being constantly redirected back to /page, we have to use /pageA/detail, but the other plugins only get /page and only provide /page/detail, so there’s some logical issues happening somewhere…

To mitigate this issue, we’re working on developing a custom function in our child theme to handle 3.0 and greater, but it would be nice if we didn’t need to. I’ll drop that function in here if it’s created before the dev responds.