Encrypted messaging app Signal is seeing a wave of new users after Tesla CEO Elon Musk told his Twitter followers to use the service.

The flood of sign-ups on Thursday briefly caused Signal to delay sending out the verification codes needed to activate new user accounts. Nevertheless, the nonprofit behind the app said it’s ecstatic about the surge in activity.

Verification codes are currently delayed across several providers because so many new people are trying to join Signal right now (we can barely register our excitement). We are working with carriers to resolve this as quickly as possible. Hang in there.

— Signal (@signalapp) January 7, 2021
Hours earlier, Musk tweeted to his followers “Use Signal” in an apparent attempt to discourage people from using WhatsApp, a rival messaging app owned by Facebook.

Use Signal

— Elon Musk (@elonmusk) January 7, 2021
The tweet arrived after WhatsApp announced a new privacy policy covering how it can share user data with Facebook. The practice is nothing new, but the policy update grabbed headlines over concerns users will have almost no way to keep their WhatsApp data separate from Facebook—a company with a notorious record on digital privacy.

On early Thursday morning, Musk chimed in by posting a meme depicting Facebook CEO Mark Zuckerberg brazenly lying to a child about the data his company can collect.

Signal ooo.
I hope it can give me signal when I dey our farm sha..
Cos once you enter that farm, he go be like say you don enter where worst pass naija