It could be a timeout in IPFS. We have seen cases where SharePoint produces timeouts because it takes longer than 30 seconds to respond.
The default data connection timeout in the SharePoint settings is 10 seconds. If the data connection is taking longer than 10 seconds to connect, expect to get an error. Increase this timeout value to resolve the issue.
1. Go to Central Administration for SharePoint
2. Click on General Application Settings
3. Click Configure InfoPath Forms Services
4. Look for the Data Connections timeout section and increase the values.
5. Then try to reproduce the issue.
Hope this helps!