False information on my PAYE summary - potential fraud?

I’ve had notification of a tax code change. My HMRC account now shows that I have 2 employers. I have never heard of the one that has been added, and have never worked for them. How can I rectify this? I have one form of employment and have done for the last 5 years.

Hi Martine,
I am unable to check personal records through the forum. You should contact our helpine so we can review the information we hold with yourself using methods on the following link: Income Tax: general enquiries.
Thank you.