Pattern fill? Fill Tool?

[PepGold]

Say I create a repeatable pattern 1000x1000px and turn it into a symbol. How do I then fill shape with that symbol? The closet possible solution I've found it exporting the symbol as a .png and using the Fill Tool and select Type: Bitmap and load in the exported .png. But it doesn't keep its original size, but scales to fill the shape. And I can't tile it. If I select Extend: Repeat I would except the bitmap to tile, but it doesn't.

What am I missing here? I don't get it.

(Artboard1 is just the Symbol duplicated 9 times. What I would expect the Fill Tool to do)

[G13RL]

You don't have to create a symbol for this unless you have a good reason for it.

Choose the bitmap, lock the padlock and choose "Wrap" to get the pattern repeated.