This is common question that we get and is probably related to expectations on how funnel stats should behave. Here are some brief concepts to keep in mind when working with your funnel stats:
1) Only unique impressions are counted, which are cookied for 12 hours. After 12 hours, they can be counted again towards impressions.
2) Impressions from the funnel creator are never counted, to avoid counting your own visits against your account impression limits.
3) There's a 10 minute cache for stats updating on funnel views.
If after this, you still think there is a problem with your stats, please do contact our support team with as much details on the issue that you can, and we would be happy to take a closer look.
Reordering the funnel steps (and then putting them back in order again) "jolts" the system to get stats working again.