Besides the actual colors being checked in the contrast tool, there are other factors that determine if the contrast ratio is sufficient. For example, whether or not a contrast ratio passes in the contrast checker also depends on whether the element is considered "Small Text", "Large Text", or a "UI Component". Regarding WCAG conformance, as long as a contrast ratio passes as AA for the appropriate type of element, it is sufficient! However, it is best practice to ensure it passes for AAA too.
For additional support, review your color combinations with the WCAG Color Contrast Checker from Accessible Web.