Hi
HMRC will never send notifications of a tax rebate / refund by email. You can find examples of phishing emails and bogus contacts at
Examples of HMRC related phishing emails, suspicious phone calls and texts Is the email about a tax refund?
You should run any antivirus software as a precaution if you have opened an attachment.
If you have disclosed personal details please forward brief details to HMRC email address -
security.custcon@hmrc.gov.uk
If you think you have been the victim of an email scam and have disclosed your bank details, please tell your bank / card issuer as soon as possible. You can get further advice and information about phishing and online security at:
HMRC phishing and scams: detailed information
You can get more information on 'Phishing and Scams' from the gov.uk website gov.uk/dealing-with-hmrc"