Hi, Jose -
Please verify that you're using a supported version of Gurobi (currently anything from 7.0 to 8.1; see https://sei-international.github.io/NemoMod.jl/installation/#Solver-compatibility-1). If you are, the problem is likely due to a fault in Julia's Gurobi package. Open Julia, and try running the following commands:
julia> using Pkg
julia> Pkg.build("Gurobi")
Then reply back here with the output of the second command. This will help us troubleshoot the problem.
Thanks,
Jason