12-yr-old Nokia 1200 ("no matches" in "Related Device or Service" box.) The new SIM card arrived out of the blue - I hadn't received the prior indication which the letter mentioned. Inserted new SIM exactly as instructed in letter. NO warning given that it might be incompatible with my phone, but "SIM not valid" message is permanently on, and switching on & off makes no difference. I swapped the old SIM back in so phone now works - but for how long? HELP! Phone is used only for emergencies e.g. car breakdown, late for appointments. I don't want to buy a new phone, and why should I anyway? Am angry! What are you going to do about it?