Media Uploader's settings go back to default every now and then
I've purchased a Media Uploader add-on, which works fine, but I have an issue with it. I'm using LearnDash LMS plugin and want users to be able to upload files in comments section in LMS topics. That's why I tick checkbox next to sfwd-topic in Uploader settings. This works fine, but after some period of time I start getting messages from users that they don't see uploader buttons any more. I check settings and see that the checkbox has gone, so I tick it again, save settings and everything is repeating again - it works for some time, but then settings are reset to default. The funny thing is that we've been using the uploader add-on for more than a year already and it worked fine until some resent update a few months ago.
Any help or advice, please?