Mastery rank 20 test completed succesfully, but doesen't rank up

Sorry for that :(  We're looking at a potential solution that addresses people having connection issues while trying to submit their successful rankup result to the server.  Normal missions will retry many times to save your results if you are having network problems, but it seems that the mastery tests do not.  Our hope is that by adding "Retry until server acknowledges" to mastery test, it will avoid this problem. Keep a look out in future updates.