We have started collecting data for a large project. When testing Survey 123 with 5 Android devices (Samsung S5 Neo) in the field we encounter a problem. After taking 12,13 surveys with no issues all devices experienced Survey 123 not responding after clicking the Survey Completed Check mark roughly at the same time. We were able to scroll up and down, but nothing else. We also couldn't close the survey. The "Confirm Close" options were not available. The only option was to force close the application and reopen it. The collected data for this record was lost.
Do you have any suggestions of why this could happen? Most surveyors were connected/logged in to Survey123/ArcGIS Online. The 5 surveyors were entering different data when this happened (not exactly the same record).
Any suggestions\ideas would be greatly appreciated.