It tries on 3 networks.
“how many times did it send the location update request?”
That’s random. Sometimes only 1 request, sometimes after 10 requests or more.
As I understand it tries 4 times the same operator, and if it’s failed it tries another.
Yes it’s a location update reject. but I think only the operator could log the exchange between VLR + HLR, right ?
I already ask to the swiss operator to to this job, but quite complicated, it seems they only have 3 days of log with roaming operation, and they are not fast to react.