I was actually talking about the price - fortunately app already downloaded.
I would expect it will be back again - almost certainly a temporary glitch, possibly due to updated version coming? (that’s a guess, not an informed piece of info)
If you can’t wait for it to re-appear on PlayStore, then you can always side-load the most recent version (1/19/20) as an apk
https://www.apkmirror.com/?post_type=app_release&searchtype=apk&s=EUFY+Security