Cost Explorer Discrepancy

Hello! When I access Billing and Cost Management home, I can see the cost breakdown from the last 6 months very consistently (around $1k per month) But when I click on Analyze your costs in Cost Explorer, or if I just click on the Cost Explorer (New) menu, I can only see the costs of last Sep and Oct, but from November to Feb everything costs like 1 or 2 dollars and there is a "Data Transfer" item that is equal to the negative sum of the other items, so it all shows 0.

Why can't I see the cost analysis of the last 4 months?