It prob is due to the third party bins i never had a good 7 day epg and if you have it set for 7 day then it is so slow to scan up and down pages the delay will drive you mad.
But did you try to hit the recive guide in menu after you set to 7 day epg if that does not help then it is in the 3rd party bins and you wont be able to get 7 day only 3 day