I had the automated HMRC one yesterday. The grammar etc was so bad that in theory someone should be able to see straight through it, but . “This is to let you know that a tax fraud has been committed against your tax account. You need to press one to speak one of our advisers straight away or the fraud case will be proceeded against you and you will get arrested shortly.” 
I actually did laugh out loud at that, but part of me was disappointed that it wasn’t a real person so I could play them along for a bit (it’s boring in lockdown....
)
But this morning I’ve read a post elsewhere about the latest COVID scam where they call you to tell you you’ve been identified as part of the track and trace process and that in order to be tested you need to part with £500 for the testing kit and results... Obviously this is a scam, but people will fall for it unfortunately.
So I want them to call me. I want to toy with them for a while, and maybe while I’m doing that it’ll keep them away from someone who is more likely to fall for it. And besides which it will keep me entertained.
.