Because your store has carrier-calculated shipping — and that is good news, not a restriction.
One category or the other
The plan picker shows two kinds of plan, and every store qualifies for exactly one kind:
- Postcode — for stores whose Shopify plan has no carrier-calculated shipping. Prices are worked out in advance and written into your shipping settings.
- The Carrier Calculated plans — for stores that have it. Every checkout is priced live, for the exact cart — see Live rates at checkout.
The other category stays visible but marked unavailable, with the reason on it — so you always see what exists, and why it isn't yours.
Why they don't mix
The Postcode plan exists for stores that cannot use live rates — it is the way to get postcode pricing without carrier-calculated shipping. A store that has live rates already has everything the Postcode plan does, done per cart instead of per band. Letting it buy the lesser mode would only be a way to get worse prices for less money.
If you want the other category
Which category you're in follows your Shopify plan, not anything in this app — see Eligibility and Shopify plans. Change your Shopify plan or billing, reopen the app, and the picker follows.
Every plan starts with a free trial
Fourteen days, once per store — so picking the right rung costs nothing to try.