I am running a WordPress website and have good traffic. But for some days I am receiving high traffic that is being sent from fake referrers. And I am really losing my all ranking keywords from Google. Even I have already lost many of my keywords because of these spam referrer attacks.
The fake referrer is not a website instead it shows "-1" as a referrer from where I am receiving traffic. I have tried searching on Google about this "-1 referrer" but I couldn't find anything that can fix it.
I will attach a screenshot below as well.
Please somebody help me so that I can stop this fake referrer, and I can regain my Google rankings. Please help me.
This is the image of the fake referrer:
Note: I am using the Jetpack plugin for my website statistics.