I went over to Correos, waited for my turn patiently (nowadays the mail service is really overloaded by Haitians). When I got to the desk, I sent the Tax Return and the NR5 form via "regular" mail, and sent the benefit application via "registered" -- what is really certified mail. Apparently "registered" mail is a service that no longer exists. So, I sent it all off and went my merry way.
When I got home I started tracking. Everything great. Processed just fine, it went hither and yon (as it does) and finally wound up at the airport.
How nice, it got on the plane! Meanwhile, at Canada Post...ESTADO DEL ENVIO FECHA OFICINA
ENVIO DESPACHADO AL PAIS DE DESTINO 25/05/2018 15:38 AEROPUERTO
DISPONIBLE PARA SALIR AL PAIS DE DESTINO 25/05/2018 15:30 AEROPUERTO
RECIBIDO EN OFICINA DE CORREOSCHILE 24/05/2018 5:28 CEN CENTRO TECNOLOGICO POSTAL
It stayed like this for days before I called Canada Post. They told me it must still be in customs. I called every few days to see what was happening, still nothing. Finally, I started calling Service Canada, asking them if it had arrived. Nothing. I called Canada Post and THEN I got someone who explained to me, that if you send something "registered" or certified, the tracking stops at the border. OHHHH, why didn't anyone say so. This person told me that if you want your mail to be trackable, send it as a small parcel.Tracking No. Date / Time Description Service Type
RRnnnnnnnnnCL N/A We could not find this Tracking Number in our system Find out why. You can edit this Tracking Number. N/A
The last chapter is this: I kept calling Service Canada to see if my mail had been received. I also checked with CRA (Revenue Canada) to see if my tax return had been received. And voilà! My tax return showed up as received, sent by REGULAR mail. I immediately called Service Canada again, and there it was, the mail had been received. So much for certified mail. And of course, as we all know, when mail gets sent to us from outside Chile, it takes at least eight weeks. Of course, Canada Post's tracking still says the same thing.
In any case, if you are going to send mail to Canada and it has to be tracked, send it as a small packet instead. Costs more, but the tracking will work.
By the way, use GMAIL to call Canada. It's free.