It may take up to 21 days after closing date of a survey for points & status to appear in your account.
The closing date can be found in the survey invite. The date in the points history is NOT the closing date, but an approximate date you were invited to participate.
Point allocation and survey status go hand-in-hand. This is why checking your history immediately after you have completed a survey will not give you an accurate answer.
If you have any doubts whether the survey went through successfully, you can check simply by re-entering the survey via the link in the invite. This will give you an indication of your status.