I believe I know what is happening here, though I concur it should be addressed.
There appear to be certain goals whose rewards will only be triggered not only after a player has obtained them -- and rightfully so --
and after another reward has also been obtained. It can result in unexpected lulls in completion of goals and then multiple goals seemingly obtained one right after the other where is no seeming connection between some or all of them. (Other than the fact they're for the same game of course.
)