Self Assessment - Uniform Tax Relief

Hi, I am currently submitting my self assessment return to pay the high income child benefit charge. I am paid by my employer via PAYE. I currently also receive uniform tax relief of £60 a year and my personal allowance is £12630 but when it comes to my tax calculation for last year it has my personal allowance of £12570, so even though I paid the correct amount of tax last year through PAYE it is now calculating that I need to pay this back. There doesn't seem to be an option to add this on the online self assessment form. How can I change my personal allowance on the calculation to reflect my personal allowance of £12630 ?

Hi Craig,
If you receive the relief for laundry of a uniform of £60 then you claim this on the employment page on the Self Assessment.
On the employment page there is a question do you want to claim expenses while working for the employer.
You would answer yes to this which opens up the expenses section to claim the £60 relief. 
Thank you.