Filling floor below player?

I'm not sure where I'm going wrong with the fill command.

I made too bubble columns for a guardian farm and even on decreased particles it's lagging me out.

I need to replace the soul sand to stop them so I can get in the area and fix some issues.

I tried with both specific boundary coords and relative coords but it never changes any blocks:

/fill 1184 39 -2289 1153 39 -2255 minecraft:soul_sand replace minecraft:gold_block
/fill ~-20 ~-5 ~-20 ~20 ~5 ~20 minecraft:soul_sand replace minecraft:gold_block

Solution 1:

The syntax is the other way around:

/fill <coordinates1> <coordinates2> block_to_be_set replace block_to_be_replaced