“Operation cancelled” popup on iOS The following screen has popped up without any user interaction. Already twice in the afternoon.
I have been wrongly receiving SMSs from an Apple service provider telling me the part I ordered has been delivered. I've contacted the company to see if it might be them. I also use salt as a cellular carrier.

How can I trace or stop this?
this clearly comes from your provider.

Most probably it is a new network profile which could not be downloaded. 
simply restart the iPhone once. So it dials into the network again and the problem should be solved.