Survey with repeats, non-federated server, Survey123 field app hangs at "Sending Data"

[TobiasFimpel1]

When I make a Survey from an ArcGIS Server Feature Service (registered with ArcGIS Online) I run into the problem that my data is submitted correctly (I can see the new insert in the Geodatabase) but the Survey123 Field App gets hung up at "Sending Data". This problem only occurs when a repeat section is included (meaning a 1:m related table in the geodatabase).

Is this a known bug? Does anybody see the same problem? Does anybody know a likely cause or workaround?

I attached the log file in case that gives you any clues. 

[TobiasFimpel1 · Accepted solution]

Setting the forward label and the backward labels of the geodatabase relationship class to an identical string value that is not <blank>/null resolved the problem.

[YukoYokozawa]

Hi! I have the same problem and found your solution. But I'm not sure how exactly to fix the problem. I checked my relationship class, and the forward and backward labels were not identical (Forward has the child table name, and the backward has the parent table name). You are saying make them to same labels? And they shouldn't be blank. Am I right?