Duplicate salary on my HMRC account, now paying higher tax than expected

There’s some duplicate payment for the last 3 months on my HMRC account and also my tax is higher than it should be with a “K” code. I did the calculations using my total income for the FY and estimated tax to be paid according to HMRC calculator. And based on the tax I’m paying currently I will be overpaying by a lot by the end of the year. Same thing happened last year and I got a refund afterwards, but I’d rather not wait for that and get this sorted. Except I’m not sure how, there no option I found to correct the employers other than adding a new one. Any ideas on what I can do here? I’m new to the UK (8 months) so apologies in advance if I am asking an obvious question.

Hi Nil.

If you contact our Income Tax helpline we can view the position.
Your employer may need to send an amendment to HMRC if the income is showing as duplicated.
Income Tax: general enquiries

Thank you.