Hi JoaoPaixao,
thanks for your response. The relation was pointed out to be wrong by OSMI:

https://tools.geofabrik.de/osmi/?view=areas&lon=-7.66023&lat=40.26185&zoom=9&baselayer=Geofabrik%20Standard&overlays=duplicate_node%2Csingle_node_in_way%2Cduplicate_segment%2Cway_in_multiple_rings%2Cintersection%2Cintersecting_segments%2Cring_not_closed%2Ctouching_rings%2Crole_should_be_inner%2Crole_should_be_outer%2Cinner_with_same_tags%2Cways%2Cduplicate_node%2Csingle_node_in_way%2Cduplicate_segment%2Cway_in_multiple_rings%2Cintersection%2Cintersecting_segments%2Cring_not_closed%2Ctouching_rings%2Crole_should_be_inner%2Crole_should_be_outer%2Cinner_with_same_tags%2Cways

Have a look here about how to edit realtions properly:

https://wiki.openstreetmap.org/wiki/Relation

The validator of JOSM showed the same error:

https://wiki.openstreetmap.org/wiki/JOSM/Validator

If you like to fix this yourself I can revert this change.

Kind regards
Guido