Honestly we have been dealing with this since may of this year. Amazon admitted to us it was an internal team (After months of them denying it) that was doing this and that they had "no control" over this ( we have the support email to prove it). They took styles that were out of inventory, cannibalized the relationship (we only list as single product not variation families) then took whatever product they wanted and separated them form their parents and then placed the children under that style calling all the products the same name which they all had different names and different fabric contents and where different product entirely i suspect based off the product rating since machines dont know the difference i guess. our returns went through the roof and we were taking serious hits to our IPI score. They did it to over 140 styles that they placed under 10 parent/root ASINS and since they changed the bulk upload sheets like twice this year i had to create all new sheets for them and it took forever. After this, the very next week, they did it again. We were able to get them to undo it but i'm still going through and recreating parent child relationships as of the time of writing this reply.

The resolution: You need to open a brand registry ticket if you are the brand owners and signed up for brand registry. Only they can undo the changes. They will send you an email stating they took the appropriate steps but they will never tell you what the steps are opting to stay behind their policy walls. Dont let it go on for to long because it can snowball out of control and you will spend weeks fixing everything. Honestly, i had no idea there was even a name for Amazon taking over your listings that you created as the seller but the name "relationship sticky delete program" is perfect. guess they teamed up with the Sticky Bandits from Home Alone.