I had this once at an employer, they wanted my email address to have my name spelled wrong in it. I noped out.
My response to HR and IT would be "This is an unauthorised change to recording of my personal data, my name, and under GDPR article 5D CompanyName and agents have an obligation to process my personal data accurately and correct inaccuracies in a timely manner. Please correct my name in your systems to CorrectName which it was from StartDate to FailDate. Should you fail to do this, I shall require proof you have reporting CompanyName to the ICO for breach of GDPR article 5D within 72 hours of my email sent time, or I shall be making my own Data Protection Act complaint and internal grievance against CompanyName. I shall also not be responsible for any work I am unable to complete during this misprocessing of my data".
I don't fuck around. Either get my data right, or I'll smack people with the GDPR and threaten ICO. I once started sending 12 hour count downs to the DWP who eventually backed down from their "it's impossible, we don't have the data, you have to resend" position to "we found your data".