Sending push notifications is a powerful way to re-engage and connect with your users. If you are having trouble setting up push notifications, make sure:

## 2. Your users have Properties called “iOS Devices” and/or “Android Devices” on their profiles

Double check profiles to which you’ve attempted to send a push notification to ensure they have at least one of these properties and that the value of the Property is stored as a list:

If not, Mixpanel’s client-side libraries can be configured to set users’ device tokens as Mixpanel People Properties once they click to accept push notifications. If you have access to the user's device token and want to set them as People Properties explicitly, you can set them using the following property names:

•  $ios_devices •$android_devices

If your users had an iOS Devices or Android Devices Property before attempting to send a push notification but these Properties were removed after sending the message, then there is likely an issue with your certificate - read more.

## 3. You’re targeting users correctly

Messages can only be sent to users with a People Profile in your Mixpanel project. If the parameter specifications of your targeted message don't match any of your users, then no one will receive your message. Ensure that the device on which you expect to receive a push notification was, in fact, targeted in your criteria.