[Resolved]  Ferns N Petals — [protected]- order accepted without stock

The order was accepted by ferns n petals and the amount was paid fully.
After that, there is no update on order status from ferns n petals and the delivery date was overdue without a delivery.
On reaching to ferns n petals customer care, they nicely said, there is no stock with their vendor.
My questions are,
1. Why they accepted an order when they don't have stock
2. Why they didn't inform priorly about their no-stock even after accepting the order
3. What ferns n petals wanted me to do during placing orders to verify the stock availability in their vendor warehouse.
4. Why ferns n petals not adding interest on order amount while refunding for the non-deliverable order, as they are holding customer amount for those many days.