4 weeks ago
Have been swapping regions now for over a year and still not resolved the issue
visited the Apple Store yesterday where they told me virgin had admitted this was an issue/error on their network.
no information on any resolution!!!
come on virgin
I found the solution a good while ago and posted it... The cause is dial assist.
Switch it off in the settings and that was the end of problem for me.
Thanks for reaching out, sorry to hear you this is still effecting you after almost a Year, have you tryed the fix as advised in the below post?