I should clarify, my words there aren’t intended as a slight on Ms Milner’s article. I had a quick search for her and it’d seem she’s published some decent, credible stories.
Despite being printed in the Daily Andrex, her article here has some decent advice relevant to the OP. In particular, the bits I’ve highlighted here:
Register for the Telephone Preference Service (TPS) free on 0345 070 0707 or at tpsonline.org.uk. Firms will then be breaking the law if they make unwanted sales calls.
The TPS today launches a free mobile phone app called TPS Protect which rates incoming calls on a ‘trust score’ of one to five. Five means the caller is from a firm with low complaints. One means it is a suspected scam.
BT customers can get its free BT Protect service that won’t allow calls from nuisance numbers it is aware of. You can add 100 other numbers to your blacklist.
Sky Talk Shield is free for its broadband and landline customers. It asks callers to state their name then plays it back to you so you can decide whether to take calls. You can block up to 1,000 numbers.
Trading Standards has 1,500 free TrueCall call-blocking gadgets to give away to vulnerable people. You can also buy the device for £100 (truecall.co.uk or call 0800 0 336 330).