Installation of mapping domain

I have a new wp on hostgator and the first thing I did was turn the site into MU.
The second to purchase and install the domain mapping plugin.

I installed everything but that the mapping does not appear in the tools section in the child theme

Can you help me?.
thanks

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Tengo un nuevo wp en hostgator y la primera cosa que he hecho es convertir el sitio en MU. La segunda comprar e instalar el plugin mapping domain.
He instalado todo pero no sale el mapping en el apartado tools en el tema hijo