Using iCloud your data is secure, you will not loss data using cloud.
You will get back last updated data from cloud.

Here is first steps for data loss issue:
Please make sure few things:

1. You have selected same data storage in both devices, you can check it from:
   App Settings >> data storage.
2. You are using same iCloud id in both devices.
3. Same default company should be selected in both devices.
   If all things are proper and still persist with same problem then try by restarting your device in which you are facing sync problem.

If still issue there try this:
Sometimes sync stops working because of data conflict issue in multiple device.
Restart your device and after restarting wait for some times.
Still you are not getting data then please try by clean local cache, you can clean local cache it by following below steps:

1. App settings >> Delete All Data >> Clean Local Cache
2. After clean local cache, please wait for some time so app can fetch fresh data from iCloud.

- Moon Invoice