Mine seems to have developed this same issue. It will return if i manually push it back into place.. If I can get an allen wrench in there, will see if loosening will help at all. There does not seem to be much force needed to return the gate by hand, but seems to require alot of force if I press where the spring on the mechanism is attached, far more force than I imagine that spring could possibly produce..

But one question for anyone who can.. When running the diagnostic to test this, when you test does the gate swing open the first time you test it, and then return the second time you test that function.. Or should the diagnostic open and close the gate on one press..

Was able to correct this issue by loosening the hex bolt under the playfield that holds the gate post in place. Then needed to raise the gate a small amount (was a tight fit, so needed to force it some).. As soon as there was a bit of a gap that could be seen with the plastic bushing (and slight vertical play with the gate), was all well..