So I’m self employed and this is my first self assessment to complete.
I completed my own self assessment on Sunday and although I have done what I assume to be correct I was dreading a call from HMRC telling me I’ve made a mistake.
Anyway Monday lunchtime I received a phone call and I picked up and got an automated message saying I have been contacted by HMRC regarding my tax calculations and hold to speak to an agent (which I did).
Agent picks up after 2 or 3 mins hold and starts telling me I have made a miscalculation with my self assessment and I am being issued a penalty.
Obviously I started stressing out and was keen on sorting the problem there and then so the agent asked me to confirm my contact details for security and I did - all my details then the agent proceeds to telling me I made a miscalculation and was I aware of this and then the phone cuts out. I tried to call back but the phone wouldn’t connect; that’s when I realised I’ve been blocked and just given all my details including NI number to a stranger 
I called HMRC straight after and told them about what happened and told them of the number who called and so on and they have said they will be monitoring my account to ensure someone doesn’t try and claim some sort of tax rebate in my name however I’m still stressing and I’m wondering is there anything else I need to do or anyone else I need to call to ensure I’m not scammed?
Thanks