Adding contour values to Contour List tool of ArcMap?

Question

I use ArcMap and I have a bathymetry raster (ESRI ASCII). I want to produce certain contours with the contour list tool

I put the negative values of contours (depths) but I get error 000859: The required parameter contour value is empty or is not the type of multiple value.

I have tried several formats (space between values, put them in brackets, square brackets) but nothing

Is there a problem due to the negative contours or I have to prepare in someway the list of values I want?

Answer 1

As commented by @FelixIP you need to:

Add them one by one using + button.

i.e. to do your three values

1. enter -50 in Contour values then click +
2. enter -100 in Contour values then click +
3. enter -300 in Contour values then click +