There is a particularly annoying HMRC phone scam plaguing at the moment.
The recorded message announces that you are in trouble, there is a court case lodged against you and that you have to press option 1 to hear the details/talk to an adviser etc.
HMRC are not in the habit of ringing people up to inform them they have a court case filed against them.
They send letters and inspectors.
If HMRC did phone you, they would first identify themselves, then request to speak to the relevant person. They don't have a recorded message.
If you are bored you can press 1 and have a profanity showdown with an increasingly abusive foreign gentleman. Great fun.