How can we make the Local pickup shipping option have no minimum order amount?

We have two methods of shipping but 5 different delivery zones. [free local pickup] and [zone 1-5 with different minimum purchase amounts, from $12-$35].

In the shopping cart view, the plugin works and gives 2 options correctly but if a customer selects free local pickup (with less than the minimum amount spent) when they reach checkout, they are able to choose the shipping method, “flat rate” or “pick up”, but there’s no minimum order for pick up. The system works correctly regarding the minimum amount spent, but incorrectly when it doesn’t allow the customer to finalize the purchase using the “pickup” method if the amount is below the “minimum” when it should be no minimum for pickup.

So our question is how can we prevent the buyer from changing the shipping method at the checkout stage and pay for the order anyway, even if the minimum purchase amount wasn’t reached in case they choose the pickup method?

Summary:

Different zones with different minimum amounts

Pickup option with every zone, but no minimum amounts

Choosing the “per shipping method”, the minimum amount doesn’t work per zone, as it should consider the minimum amount.