It's difficult for me to give advice because I think a working elected politician is probably smarter than I am about how to handle the push and pull of aggressive politics, including even foreign actors, but there are a few options in the tool kit. One is that, if something is blatantly transgressing legal and normative boundaries, like involvement from a foreign actor, it can be disclosed—and you might even garner sympathy for that.
However, I think that, often, if there's a false narrative circulating, there's actually a difficult decision about whether to respond to it and, thus, give it credence and maybe even elevate the number of people who are thinking and hearing about it, or whether to just let it lie because, frankly, many influence campaigns and misinformation campaigns are not effective. This is the elephant in the room. We don't know how effective many of these things are. However, many of them are demonstrably ineffective, so that's an important strategic decision.