It is frustrating that I do not have a network coverage since I left London about a week now. I started not to be able to use my mobile data and phone at Amsterdam airport and now in Finland. I seem to have done all the tricks: turning off and on the WiFi; switching off and on my iPhone; removing my "Find My Phone" feature, and removing and putting back my SIM. I have a permanent "No Service" sign with an occasional local service provider popping up very briefly once in a while. Sometimes, the phone gives me "activation required", and "carrier network requires updating" messages, but they do not continue any further.
I am sorry to hear you still haven't got any access on your phone abroad after following all our steps. so I can help further I will send you an invite into a private chat, please click on the purple envelope to accept.