I paid 20,000 for an item that was supposed to give 1000 flowers I did not get them. Why?

The flowers you receive from a decoration are never added to the number shown next to the flower icon. Since this number represents NOT how many flowers you HAVE but rather how many MORE you need to get to the next scene, the flowers you earn will be SUBTRACTED from this number.

Say it shows 220 flowers and you earn 1000 flowers, this will open 4 scenes needing 220 flowers each and you will be left needing 100 flowers to open the next scene. The flower counter will show not 1250 flowers as you expected but only 100 flowers now.

This is just an example, actually in the game each scene requires a different number of flowers to open, so it's a little more complex than that. But always the flower counter only ever shows how many flowers you need, never how many you have. So the number of flowers you earn will never be added to the number shown.

You get the flowers after construction is complete and after you remove the red ribbon.