This is caused by - 25825509 - SURVEY BUILDER IN APEX 5.1 IS NOT RECORDING SURVEY RESULTS
I am receiving the same results and using Application Express 5.1.4.00.08.
Is there a patch or workaround that can be applied?
Having the cause doe not answer how to fix.
This bug was actually fixed for our 5.1.2 patch set release, so if you're running 5.1.4 then that patch release would also contain the fixed version of Survey Builder. The app version containing the fix is 2.0.9, according to the bug. What version of the app are you running? You will find this information on the Packaged Apps > Survey Builder page, for example: