Gestational diabetes in pregnancy

So I got a call I failed my first test and now I have to go back and take the 3 hour glucose test I believe that’s what it’s called .

Has this ever happened to anyone, like you failed the 1st test (the hour test) and went back for the 3 hour test and passed....

Or once you failed the 1st test (the hour test) and went back and took the 3 hour test, you failed again....

Like how likely is it you’ll pass the 3 hour test if you already failed the 1st one...