Defining intitial value for parameters as a vector for each parameter

[Mehdilotfi7]

Hi, and thank you for your excellent package.
I am trying to estimate the parameters of an age structure model, so in this kind of model, elements of the initial value for the parameters are vectors; when I define the initial condition as above, I receive this error:
How can I solve it? Is there any method for that?
MethodError: no method matching (Vector)(::Matrix{Float64})
Closest candidates are:
(Array{T, N} where T)(::AbstractArray{S, N}) where {S, N} at ~/.local/julia-1.7.3/share/julia/base/boot.jl:479
(Vector)() at ~/.local/julia-1.7.3/share/julia/base/baseext.jl:38
(Vector)(::DataFrames.GroupKey) at ~/.julia/packages/DataFrames/zqFGs/src/groupeddataframe/groupeddataframe.jl:617

[wildart]

How do you define your initial population? From the error it looks like your population is defined as matrix, you may want to convert it into vector of vectors.