Fuss Free Phones is a mobile network with telephonist support. Taken a bit of time in coming, but it may provide a fairly priced answer to many:
https://www.fussfreephones.com/
https://twitter.com/fussfreephones
https://en-gb.facebook.com/fussfreephones/
https://www.helpfulthings.co.uk/products/fuss-free-phones-annual-subscription-and-free-phone
https://www.unforgettable.org/fuss-free-phones-calls-made-simple
https://www.hearingdirect.com/fuss-free-phones-sim-pack.html