If you are missing entries for a service, it means either your iPad was not connected to the internet or it lost internet connection during use. In either case, the iPad is storing the entries locally on the iPad(s).
Disclaimer: Never delete the Expression app off of the iPad while troubleshooting. Doing so will remove all data stored within the app, including guest entry data.
1) Open a Safari internet browser on the iPad.
2) Go to an internet address such as CNN.com or yahoo.com.
3) If the website loaded fine that means you are connected to the internet. If it did not load, you are having internet connection issues. See iPad connection issues or there could be issues with your Wi-Fi network.
!!You will need to do this step on each iPad that was used for the service(s)!!
If the above step, refreshing the app, did not work, please proceed to the next step.