I wouldn’t necessarily ASSUME it is from Real Product Talk (we have no affiliation with them other than using them for launches), but it could be possible. There could be a number of other things that you may have been linked to.
For example, your follow-up emails might have some wording in it that violates Amazon’s policies. You may be incentivizing people for their reviews in some other way through inserts or on the packaging. I am not sure, but if you can pinpoint exactly what they are saying is review manipulation, then you can appeal it by giving your plan of action to fix it.