A real script, annotated line by line
A script is not something to read. It is a record of what worked, written down so you do not have to rediscover it every call.
The technique
Every line in a good script does one job, and you should be able to name it: earn attention, earn permission, learn something, present, close, or handle. Lines that do no job are padding and get cut. Once you can name each line’s job you can improvise inside the structure; which is the whole point, because customers do not follow scripts.
1. “I’m calling about the broadband at 14 Marlow Road.” → earns attention, checkable 2. “Your street went full fibre last month.” → earns permission, gives a reason to keep listening 3. “Do you know roughly what you pay?” → discovery, answerable from memory 4. “Most people on that street are on £41 and could be on £28.” → offer, one sentence, one number
Four lines, four jobs. Anything you would add here should replace a line, not extend the script.

What goes wrong here
Label every line in your own script with its job