Thanks everyone. Each post was enlightening.
Indeed, I'd got too many digits but it was just another 0 on the end so would have not affected things in the old days, but the 'smart' phone divided the number up based on being confused. That and having a confused owner did not help.
Since each country is different, it is abbreviated to a + symbol
Yes, but erm somewhere something in the phone must know what to send out . . . unless all countries agree to this new protocol.
Having made changes to my main list, I forgot about it, until feeling a pleasurable vibration on me left nipple. I grabbed the phone and there was no doubt it was vibrating* but nothing on the screen. Finally, and I still don't know how, I received a high definition picture of my pal's head and agreed to Skype on big screens where we were able to play with phones and sort out the final issues. Great, but still the logic of answering was clouded. This is when I Edited the number and allowed Notifications. One or both corrections seemed to resolve the issue, though one has to be very aware of the difference between CHATS and CALLS lists.
I now find there's no family consensus between WhatsApp and Signal. The Rivetess favours the latter, I assume because she's naturally secretive.
*Vibrations. For years I've felt vibrations from the phone. It's so feint that I'm not certain, but it is consistent in its teasing. Now I've read an article that says this is very common and that the vibration is generated in our minds because of an anticipated sensation. I find it had to believe, but stranger things . . .