Can slope be added later in a walk-in shower?

Hello, we are currently renovating our bathroom. The bathroom previously had a walk-in shower, but no slope was installed towards the drain. How could this be resolved? I have attached a picture of the situation. It is a point drain that goes down about 40 cm vertically. The shower area should be as before, 120 x 120 cm.

Hello, we are currently renovating our bathroom. The bathroom previously had a walk-in shower, but no slope was installed towards the drain. How could this be solved? I have attached a picture of the situation. It is a point drain that goes down about 40 cm vertically. The shower area should be as before, 120 x 120 cm.

The slope is created via the screed, so you have to break out and redo the screed if you want it to be level with the floor.

Attached a picture of the situation.

Where?