How many days you spend in the UK and how many in Poland? Then I can advise further
Thanks for your response
Then your tax position will be dealt with in Poland as you will be treated as not resident in the UK, (as you spend less than 901 days in the UK) and any UK tax suffered you then claim as a tax credit against your Polish tax position (or if you have claimed a UK tax refund or paid no tax as you advsie this is self employment then just declare the income to the Polish tax office.
You cannot have your whole tax position dealt with in the UK I am afraid and whilst you can pay Class 2 National Insurance - at year end your earnings are below the limit of the charge arising, but can choose to pay these voluntarily (through self assessment)
You are best trying to find a tax adviser in Poland who speaks English (of which there will be many)
Let me know if I can assist further