There are a few things you can try to get the sync to kick off.
Firstly, you must make sure the mobile app is syncing to the correct account. If you have used this install of the mobile app with a prior account, you will need to delete the app and reinstall using you new login details.
If that is not the issue, try hard closing the app. On Apple devices, double tap the device home button, then drag the Cavanti tile off the top of the screen and restart it. On Android, tap the triple bar button on the bottom of the screen and drag Cavanti off the screen. This forces a full sync cycle and should get you out of trouble.
If it is just a single record that is not syncing, try opening that record on the web based app and adding some information, this can be simply a space, and save. Sync your device and see if the record comes down.
If this fails, you may need to delete the app and reinstall. BUT, any data on the device that has not sync'd will be lost when you delete the app from your device, so make sure to enter any unsync'd data onto the web based app before deleting and reinstalling. Please note that on Android devices you must have the 'backup from local data' feature turned off for a delete re-install cycle to be effective. We need your clean data to come from our database in the cloud, not from the local device which may contain a corrupted piece of data preventing the sync.