scikit-opt with VRP problem

I'm a debutante in the optimization problem with metaheuristics. I have tried running the vrp example with the immune algorithm. But, the result shows one route while the vrp problem must return multiple routes that are equal to the number of vehicles defined as an input parameter. To my best knowledge, the vrp problem is an extension of mTSP problem (multiple traveling salesmen problem) not a TSP problem.

Could you please help me to run the immune algorithm in vrp problem using multi-objective and constraints in order to obtain optimal routes for multiple vehicles?