placing meta tags into the head

Hi,
I need to verify some social networks which require me to add metatags into the head. I added the metatag into my theme’s head and it works when logged in, but does not work with coming soon enabled. Not in the head when I check source.

Is there a way to add metatags to the head of the plugin?

https://www.ads-software.com/plugins/coming-soon-by-supsystic/