You can get plundered up to 3x max, so if people bounce against you 3x you will no longer appear in the plunder list. This is also why you normally dont get support that can be easily countered (eg: blitz), where if people test you, all they have to do is get some hard counter (hinata, han, etc) and beat you again. Of course....if you sync up with the person who is supporting you, you can try countering the counter if you want to be fancy :P