Why does traffic or conversion rate show as unavailable?

Because Shopify has not let nouz read your store's traffic yet. Traffic means the visits to your shop, which Shopify calls sessions. nouz gets them only from Shopify's own reports. Without visits there is no conversion rate, the share of visits that end in an order. So nouz shows no rate instead of guessing one.

You see this on Insights, in two places. One is the Conversion rate card on the Revenue tab. The other is the Traffic and conversion card on the Marketing tab. Without traffic, their bars stay empty and the rate reads –, the app's sign for no value.

Shopify needs two things before an app may read its traffic reports. The first is a reports permission. The second is Shopify's approval of the app for the level of customer data those reports hold. One of the two is missing.

If your store was connected before nouz asked for the reports permission, open nouz from your Shopify admin, under Apps, as an owner or admin. Shopify then shows its approval screen once. If the permission is already there, Shopify has not approved nouz for that data yet, or your Shopify plan does not include the reports.

A store connected through a direct install link gets the access from Shopify's Grow plan upward. Ask support if you are not sure which case is yours.

Visits are only for analysis. They feed the conversion rate on Insights, and nothing on the P&L. So every other number in nouz is complete, whatever the traffic says.