iOS App Reports crash/freeze while loading

We shared an App with a dashboard and several reports with Pro content to about 30 other Power Pro licensed users. Some of these users are giving feed back that when they bring up the reports the app seems to only partially load data. Most of the reports are just tables with some slicers. Affected users are on iPhone 6 and 6 Plus. Running IOS 11.2 and Power BI app ver 14.2. We have had them try to reinstall. But that did limitless to help. Can anyone assist trouble shooting this behavior? Thanks in advance.