You elaborate further in a comment that all correlations are reported as 1, 0 or -1.
Since the correlation coefficient varies between -1 and 1, the evidence strongly suggests that you get rounded numbers: correlations between -1 and -0.5 are shows as -1
; correlations between -0.5 and 0.5 are shown as 0
; and correlations between 0.5 and 1 as 1
. Surely this is not what you intend.
Why the output is rounded is not clear (have you changed any default settings?) and the issue is not reproducible. Here is what I get when I repeat your steps:
library("DescTools")
Desc(price ~ delivery_min, d.pizza)
#> ------------------------------------------------------------------------------
#> price ~ delivery_min (d.pizza)
#>
#> Summary:
#> n pairs: 1'209, valid: 1'197 (99.0%), missings: 12 (1.0%)
#>
#>
#> Pearson corr. : 0.095
#> Spearman corr.: 0.080
#> Kendall corr. : 0.054

Created on 2022-07-27 by the reprex package (v2.0.1)