In article , Mike
Barnes writes

It would make more sense for all concerned if the other house's name was
changed. But to answer your question I changed the name of my house
(which I thought didn't have a number, but it turns out it did) simply
by having a nameplate made and drawing the postman's attention to it.

At last some sense, "Excuse me, you appear to have named your house
the same as/similar to mine, as this is bound to cause confusion please
change it forthwith". As to asking Royal Mail if they wouldn't mind
changing, you don't, you tell them that it has changed and let them sort it
out (mind you the bit about just telling the postie is eminently sensible,
IME the men on the ground are very helpful and seem to be capable of
sorting out many problems themselves).
--
fred
Plusnet - I hope you like vanilla