QBSE How can I set my personal tax free allowance to zero ?

Welcome to the community, Terry. In the UK, pension income is taxable and is added to your self-employment earnings to determine your total taxable income.    

Since the standard Personal Allowance is £12,570, you will only owe tax on the combined amount that exceeds this limit. Usually, HMRC applies your tax-free allowance to your pension first. If your pension is less than £12,570, the remaining allowance can be used against your self-employment profits.    

In this case, I recommend reaching out to the agency or HMRC for better guidance and to ensure your tax-free allowance is applied correctly to both incomes.     

If you have additional questions or concerns, please leave a comment below.