HMRC penalty for not filing self assessment for FY22-23 no

[Raul74]

Hi All, Just to give some background , I am working for an employer, and a few months back observed that my take home salary had reduced as tax deducted was on higher side than the usual monthly deduction, upon further investigating and speaking to HMRC, realised that my Paye tax code changed from 1257L to some K328 in the last few months of current year.
Apparently on checking with HMRC post suggestion from my employer, I was told this was due to me not filing my tax returns for fy22-23. During the last year, my P60 showed income less than 10k for fy22-23, as I only arrived in UK and was on payroll starting from mid Jan 23, and hence no tax was deducted by my employer. But apparently I was fined because I missed filing my self assessment for previous year fy22-23. Anyone faced similar issue and any success in claiming back the penalty from HMRC by filing an appeal with HMRC by filling form sa370.... ? HMRC informed me to file paper returns for previous year Fy22-23, and along with that file a appeal using form sa370...which they will review and get back.

Note I worked in UK between 2013 and 2018, and filed all my returns . I returned back to my home country and arrived back only in Jan 23, post which it seems this penalty got triggered in July 24. Any chances to get this penalty waived off, as HMRC is directly collecting the penalty from my payroll by changing the Paye code thereby resulting in additional tax deduction

Thanks