Snookie12cat

I had a new tax code notice to say £421 will be reduced from my allowance for income on savings. I earn under £12k a year and so do not pay tax so not only have the £1k personal savings allowance but also £5k starting rate of tax. There is no way I have or will exceed this in the next tax year so why is my personal allowance being reduced to tax my savings? Can you explain how I can get this amended or what will happen if I pay tax on my savings when I do not need to? Can I get it back?

My new tax code for 24/25 has a tax code of C1117 due to marriage tax allowance and other things. But I can see they have reduced it by £421 to account for savings interest. Due to being a low earner I do not earn over the threshold so not only get the personal savings allowance of £1000, I should also get £5000 starter rate of tax, meaning all the interest I earned last year, which is under £6k, should be tax free. How can I get this reduction removed? and if it does not get removed, how will I get the additional tax back if its taken by PAYE? Why would HMRC levy this charge when I am not required to pay tax on my savings?