It’s the world’s most popular messaging app with 3 billion active users. Most of you will have WhatsApp on your phone. And while the RCS encryption upgrade will challenge Meta’s mega-messenger, there’s a much more serious threat you should worry about.

Not all apps are real. Sometimes the threat from fake or unofficial apps can have wide ranging consequences, as per the FBI’s warning about fake Chrome apps. But when it comes to WhatsApp, the threat is simpler. You could be banned and lose your account.

You may have decided to install an unofficial WhatsApp app on your Android device for its added features. But you might also have done so through a link in a message or post, not realizing that the app is a dangerous clone and undermines WhatsApp’s security.

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If you have Google’s Play Protect running on your device, you may now see a warning that “this app is fake.” If so, WhatsApp says, “due to security concerns, Google may disable and uninstall these applications.”

The risk, the platform warns all users, is that “unofficial WhatsApp apps are altered versions developed by third-parties and violate our terms of service. We don’t support these apps because they put your privacy, security, and safety at risk.”

These third-party apps are not all malicious, but they compromise WhatsApp’s security to protect your content. As such, they’re pointless. “We don’t support these apps,” WhatsApp says, “because we can’t validate their security or privacy practices.”

The platform lists popular apps including GB WhatsApp, FM WhatsApp, WhatsApp Plus, TeleMessage and TM WhatsApp, but there are plenty of others, many targeting specific regions. Using any of them is a risk. “Unofficial apps,” WhatsApp warns, “might carry malware that can steal your data, and damage your phone.”

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Even if there is no malware or data theft risk, it’s unlikely your content is secure. The app can view it and will are no privacy assurances. “There’s no guarantee your messages or your data, like your location or the files you share, will be private and secure.”

And there are other consequences as well. Anyone using an unofficial app is warned “your account might also be temporarily or permanently banned, or it could lead to restrictions on your account, including the ability to link devices.”

Switching back can be difficult and it’s not certain all your data will transfer back into the official WhatsApp ecosystem. But you should do it anyway. “Before downloading our official app, we recommend saving your chat history, media files, and documents. Only chat history created while using the official app is supported.”