To resolve the issue of Virgin Pulse not syncing with the RethinkCare app, please follow these detailed steps:

1. Check App Permissions:
Make sure the Virgin Pulse app has the necessary permissions enabled to access RethinkCare. Go to your device settings, find the Virgin Pulse app, and ensure all permissions, especially those related to health data, are granted.

2. Revoke and Re-establish Connection:
Log into your Virgin Pulse online dashboard and revoke access to the RethinkCare app. After revoking the access, re-establish the connection between both apps. This can help reset their sync capabilities - learn more.

3. Uninstall and Reinstall:
If the issue still persists, uninstall both the Virgin Pulse and RethinkCare apps from your device. After removing them, restart your device. Once your device is back on, download and install both apps again from the App Store (for iPhone) and log in with your credentials. This method has resolved similar issues for other users - learn more.

4. Check for Updates:
Ensure both applications are updated to their latest versions. Go to the App Store on your iPhone, search for Virgin Pulse and RethinkCare, and check if an update is available. If so, install the updates.

5. Clear App Cache:
Although iOS doesn’t allow direct cache clearing, you can mimic this effect by uninstalling the apps (as mentioned in step 3). This process can help remove any corrupt data that may hinder syncing - learn more.

6. Contact Support:
If none of the above steps work, it may be beneficial to reach out to the support teams of both apps. You can find the RethinkCare support on their website, or refer to the Zendesk support page related to Virgin Pulse for more assistance - learn more.

Following these steps should assist in troubleshooting the syncing issue between the Virgin Pulse and RethinkCare apps effectively.