Threatening PM from another forum

I don't know if I posted in right place but I hope I did.
Anyway I have a rp forum for one year now and we never had any problems with others,until now.The members of the other forum that send us a message,started to coming on mine and leaving their forum,because they like mine more but yesterday we recived this message that we have 3 days to delete our forum or they will do it if we don't.
Is that posible and what I can do to stop them?

Possibly just trying to scare you.

https://help.forumotion.com/t59451-frequently-asked-questions
Just read under

To be read:
Security and Foundation

thank you for reply so if I get is right they can do anything if they don't have Founders password?

As a founder/administrator of a forum, you will find people threatening you for one reason or another. For example, I've had people threaten me because they got banned from my forum for not following the rules and were venting their frustrations at the time. You will find that when you've been threatened, it usually turns out to be an empty threat.

I would go ahead and do the things in the thread that Sanket gave you. It never hurts to be as secure as possible. You don't want someone stealing your admin password. I've changed my password before just for grins and giggles. It keeps people from guessing your password if you change it every so often.

Dont pay any mind to messages like that. I would even ban them unless they are sending through contact or report abuse tab in your footer. Yopu would receive messages sent from them tabs.

Anyway as long as you are following all forumotions TOS, moderating your forum and are not allowing violations, then i would not worry about silly messages such as that.. And if anything did happen forumotion would be able to put your forum right back up, but i highly doubt this would ever occur

Sometime people are like that.
You can ban them and report to your IP service provider.
Usually when I see such message I will delete and inform
my forum/support leader .

Thank you guys for the help it means a lot
I guess that this is solved