Good morning Liferay-Friends,
one of our customers noticed strange behaviour with the Liferay-Formbuilder. (7.1.3 CE - all security patches applied)

Scenario: Hundreds of forms, some of them submitted 1000+ times.

Problem: Some Submits ~10% remain in a Draft-State. Further analysis showed that this happens even with completely filled out forms - if checking the sent entrys in the Liferay-Backend we notice that some test-cases are missing some required fields.
On submitting the form these fields was filled correctly. It seems like that sometimes a completely filled out form that is successfully submitted will just stay in Draft-Phase with a single field missing.

Our rocky and stony path with Liferay brought us now to a problem that I really can't understand. 
Any tipps using/ improving the form builder or insights how the form builder is working would be great. 

Greetings,
Fredi