How to put email in sticky side buttons plugin?

I want to use sticky side buttons plugin and it works fine for Facebook and phone but I also want to add email and if i just enter my email there as URL I get a page that tells my “error page not found…” when i type https://[email protected] it does nothing.
How do I have to type the email in URL so it will automatically send a mail when people click the button?

Thanks alot

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