I guess I have been lucky. DH takes the daily survey first thing in the morning and as long as he gets the Congrats page, I assume we will get credit- and I don't try to take another survey (I used to check that before the survey issues a few months ago, but stopped). He has taken a survey every day this month (good demographics lol) and there was only one day he didn't get the congrats and didn't receive credit. I usually clear cookies at some point and take the SM and OTX and it has worked out well.