Missing reduced_index

[jgsimard]

Using the function mean(X, dims = 2) I got the following error

ERROR: ArgumentError: No method is implemented for reducing index range of type ComponentArrays.CombinedAxis{FlatAxis, Base.OneTo{Int64}}. Please implement
reduced_index for this index type or report this as an issue.

the type of the matrix is
ComponentMatrix{Float64, Matrix{Float64}, Tuple{Axis{(S = 1:2, I = 3:4, R = 5:6)}, FlatAxis}
and size of the matrix (6, 201)
What should I do ?