Hi Fernando,
On the License server side can you goto C:\Program Files\ANSYS Inc\Shared Files\Licensing\license_files and check if ansyslmd.lic file is the latest one? If not then upload the latest file on License Manager.
On the client side C:\Program Files\ANSYS Inc\Shared Files\Licensing and open ansyslmd.ini to check if client is pointing to the right server.